I bought the 16 GB WiFi-equipped iPad when it first came out. Like many others, I returned it a month later.
As much as I liked Apple’s latest gizmo, I just couldn’t find a way to consistently use it. Sure, the iPad was more portable than a notebook, but it doesn’t run OS X. Instead, Apple decided that the iPad should run on iOS, the mobile version of its desktop operating system.
And therein lies my problem. OS X applications don't run on iOS. That means I can't run Microsoft Office or Adobe Photoshop, the two tools that I need to stay productive. There are applications in Apple’s App Store that serve as quasi-substitutes, but paying more for a program that I already have (with fewer functions) isn’t what I need.
Whatever I gained in portability, I lost in productivity. The iPad is a solid content consumption device; it's not nearly as suited to creation. If you want to be productive, you still need a computer.
The next time you’re at an airport, watch the professionals in suits. If they’re typing a Word document, editing a spreadsheet, or uploading a file to the corporate VPN, they’re still using a notebook to do it. Meanwhile, tablet users are working on crossword puzzles, writing email, playing Cut the Rope, or browsing the Web. That’s the limitation of a tablet; it’s really more about passing time.
To be fair, there are people who can be productive with a tablet (even in the office here, there are Tom's Hardware staff who do most of their communication on an iPad). But that group is eclipsed by the number of people using tablets for entertainment. We admit it: sharing photos at a party is more fun (and easier) on an iPad compared to a notebook. If you work all day in front of a computer, plopping down in front of the TV with an iPad to surf the Web somehow feels relaxing. Pulling out the notebook and balancing it on your lap still feels like a remnant of work.
However, “fun” only stays fun if you color within the lines. As they exist today, tablets suffer a number of shortcomings, including limited Adobe Flash and multitasking support. Performance is nothing to write home about, either. Fortunately, tablets are constantly evolving. The tablets we see today are going to be followed by many more. But if you want the latest and greatest now, let’s see how far this development segment has come with an extremely in-depth look at Apple’s iPad 2.
Apple focused on making the iPad 2 thinner and lighter, and it’s a welcome relief. Holding the original iPad in one hand is quite literally a pain compared to its predecessors specifications. Right away, the iPad 2 offers a better mobile experience.
| Apple tablet comparison | iPad | iPad 2 |
|---|---|---|
| Length | 9.56" | 9.5" |
| Width | 7.47" | 7.31" |
| Height | .5" | .34" |
| Weight (3G) | 1.6 lb | 1.33 lb |
The dimensions are similar, but Apple achieves a lighter and thinner design by tapering the iPad's edges.
This has other, less immediate benefits. If you hold the original iPad for extended periods, the two edges tend to leave an uncomfortable square imprint between your thumb and forefinger. The curves of the iPad 2 make it more comfortable to hold, but the thinner profile makes this single edge slightly pronounced. There's a bit of give and a bit of take as a result, but the iPad 2’s design is a marked improvement.
The physical layout is the same as the original iPad with three minor changes:
- The iPad 2 has a slightly larger speaker. This required more space, so it’s now located on the back.
- Apple sells “smart covers” to protect the display. There’s nothing “smart” about them, though. Apple is just adding magnets that correspond to magnets located beneath the front bezel of the iPad 2. This is supposed to hold the cover in place.
- Apple adds a VGA front-facing and 720p rear-facing camera. We’ll get to this in a bit.
The back of the iPad 2 is covered by a familiar aluminum shell. However, Apple uses a different alloy compared to the original iPad. It's hard to tell from our pictures, but there is a slight blue hue to the iPad 2's aluminum. For those that remember their chemistry, this is a clue that Apple increased magnesium content, translating into more scratch resistance. I purposely took a nail file to the edge, and can absolutely say there is a tangible difference.
The original iPad actually uses the same aluminum alloy as the 2010 MacBook Pros, but neither stands up well against time. After a few months of use, you find your perfect aluminum surface marred by scratches due to little particles grinding up against the surface. That seems to have changed with the iPad 2. Now, this doesn’t mean the newer tablet is scratch-proof, so I’d still recommend a case if you want to preserve the beauty that Apple loves to market.
The button layout on the iPad 2 isn't any different, but the new curves cause the buttons to protrude a little further than before. The result of this is a bit more tactile feedback.
The 3G version of the iPad 2 sees its SIM card slot repositioned to the middle of the left side. There is nothing wrong with this tweak, but I found it extremely difficult to open the SIM slot. The curves on the iPad 2 tend to hold the SIM holster too snug, so it feels like you have to do extra work to get it free.
The curved design of the iPad 2 has one glaring weakness: its dock connector. It’s still in the same spot, but it’s no longer easy to dock. The flat edge of the original iPad allowed you to line up the cradle and the tablet. On the iPad 2, the process is still the same, but without the bottom edge to guide you. There’s more guessing involved, which results in more scratches as the cable scrapes up against the aluminum back.

Apple uses what’s referred to as a system-on-a-chip (SoC) in its mobile devices like the iPad and iPhone. In this particular implementation the SoC includes the processor core (or cores), graphics processing, and RAM in a package-on-package. Because those components sit next to each other in the same package, data transfers are achieved more efficiently. Moreover, less PCB space is consumed, since more functionality lives in one on-board component.
The influence of an SoC isn't all positive, however. A heavily integrated IC still has specific physical and thermal constraints, so the SoC's comprising subsystems aren't as potent as they might be if they were discrete.
Intel's Sandy Bridge architecture is a good example. The company simultaneously improved platform performance, while trimming power versus its previous-generation design. However, keeping processing, memory control, cache, and graphics in the same 95 W thermal window required concessions. The HD Graphics engine is perhaps the clearest indicator that Intel was working with a very specific transistor budget. Though the company's engineers created an engine deemed "good enough" for many desktop workloads, discrete graphics cards like AMD's Radeon HD 6970 and Nvidia's GeForce GTX 580 demonstrate how much more flexibility there is without the considerations afforded to more integrated solutions.
| Apple A4 (iPad) | Apple A5 (iPad 2) | |
|---|---|---|
| Processor | 1 GHz ARM Cortex-A8 (single-core) | 1 GHz ARM Cortex-A9 (dual-core) |
| Memory | 256 MB LP-DDR (single-channel?) | 512 MB LP-DDR2 (dual-channel) |
| Graphics | PowerVR SGX535 (single-core) | PowerVR SGX545MP2 (dual-core) |
| L1 Cache (Instruction/Data) | 32 KB / 32 KB | 32 KB / 32 KB |
| L2 Cache | 640 KB | 1 MB |
The iPad 2 features Apple's newest SoC, the A5, which is completely different from the A4 in its iPad. Let's start with what changes in the CPU.
| ARM Cortex-A8 | ARM Cortex-A9 | |
|---|---|---|
| Package Size | 198.8 mm2 | 238.8 mm2 |
| Issue Width | dual-issue | multi-issue |
| Out-of-Order Execution | No | Yes |
| Execution Pipeline Depth | 13-stages | 8-stages |
| FPU | VFPv3 | VFPv3 |
| Processing Power | 2.0 DMIPS/MHz/Core | 2.5 DMIPS/MHz/Core |
Instead of the iPad’s ARM Cortex-A8, the iPad 2 uses a dual-core ARM Cortex-A9 with a total of 1 MB L2 cache. At the architectural level, the major difference is out-of-order execution. This is regarded to be a higher-performance approach than in-order execution, which executes instructions based on the order they appear. An out-of-order design addresses instructions based on the availability of of input data, thereby preventing the pipeline from spinning idly as data is retrieved.
If you want to draw a summertime analogy, consider the process of preparing a glass of ice water. You could choose to put the ice in the cup before you get the water, or you might fill the cup with water before getting the ice. The quickest task depends on where you are in relation to the refrigerator and the faucet. Out-of-order execution pipelines operate similarly.
The problem is that out-of-order execution requires extra die space in order to rearrange all those operations, which means that you're using more transistors and increasing energy consumption. That's one reason why Intel's small, power-efficient Atom architecture employs in-order execution. The benefit, however, is improved performance, as fewer CPU cycles are wasted. The fact that Apple moved to out-of-order execution is indicative of its emphasis on augmenting the iPad 2's performance.
According to analysis done by Chipworks, Apple also couples its dual-core ARM Corex-A9 with 512 MB of LP-DDR2 (low-power DDR2). The original iPad only used 256 MB of LP-DDR. So, not only do we have two times more memory, we have it delivered through a more modern memory technology (DDR versus DDR2).
ARM Cortex-A9 (single-core variant)
CPU Performance
Geekbench is a synthetic benchmark similar to SiSoftware's Sandra, and it's one of the few available benchmarks available for iOS. The best part about Geekbench, however, is that it's offered on multiple platforms. That means we can use it to make apples to apples comparisons against low-power x86-based devices like netbooks.
| Geekbench v.2 Score in Points, Higher is Better | Apple iPad | Apple iPad 2 | Dell Mini 1012 (Atom N450) |
|---|---|---|---|
| Overall | 456 | 746 | 917 |
| Integer | 365 | 681 | 910 |
| Floating Point | 458 | 909 | 762 |
| Memory | 678 | 787 | 1105 |
| Stream | 325 | 323 | 1112 |
Single-threaded floating point and integer performance is much stronger on the iPad 2 than its predecessor. On average, performance nearly doubles.
The Cortex-A9 demonstrates a large lead in single-threaded scenarios due to its updated execution pipeline. However, threaded floating point performance sees an even larger boost, as the architecture's advantages are multiplied by the increased parallelism enabled by a second core. Though, I should point out that this doesn’t necessarily translate into better real-world performance. Most Apps have a greater tendency to rely on integer performance. That's the case whether you're talking about iTunes on the desktop or on the iPad.
From an architectural standpoint, we've come a long way since the original iPad debuted. But tablets fall very short of netbook-class performance. Intel's old Atom N450 still manages to outclass even Apple's latest hardware.
| Geekbench v2 (detailed results) | Apple iPad | Apple iPad 2 | Dell Mini 1012 |
|---|---|---|---|
| Integer Section | |||
| Blowfish (single-threaded scalar) | 13.6 MB/s | 13.2 MB/s | 26.2 MB/s |
| Blowfish (multi-threaded scalar) | 14.3 MB/s | 26.0 MB/s | 41.5 MB/s |
| Text Compress (single-threaded scalar) | 1.25 MB/s | 1.49 MB/s | 2.49 MB/s |
| Text Compress (multi-threaded scalar) | 1.20 MB/s | 2.79 MB/s | 3.60 MB/s |
| Text Decompress (single-threaded scalar) | 1.13 MB/s | 2.07 MB/s | 3.22 MB/s |
| Text Decompress (multi-threaded scalar) | 1.09 MB/s | 3.24 MB/s | 4.86 MB/s |
| Image Compress (single-threaded scalar) | 3.26 Mpixels/s | 3.77 Mpixels/s | 6.00 Mpixels/s |
| Image Compress (multi-threaded scalar) | 3.38 Mpixels/s | 7.42 Mpixels/s | 8.81 Mpixels/s |
| Image Decompress (single-threaded scalar) | 6.12 Mpixels/s | 6.66 Mpixels/s | 9.98 Mpixels/s |
| Image Decompress (multi-threaded scalar) | 6.04 Mpixels/s | 12.8 Mpixels/s | 15.0 Mpixels/s |
| Lua (single-threaded scalar) | 173.5 Knodes/s | 272.6 Knodes/s | 340.4 Knodes/s |
| Lua (multi-threaded scalar) | 172.9 Knodes/s | 535.0 Knodes/s | 488.4 Knodes/s |
| Floating Point Section | |||
| Mandelbot (single-threaded scalar) | 79.9 MFLOPS | 278.8 MFLOPS | 339.6 MFLOPS |
| Mandelbot (multi-threaded scalar) | 79.4 MFLOPS | 549.0 MFLOPS | 613.2 MFLOPS |
| Dot Product (single-threaded scalar) | 247.5 MFLOPS | 221.3 MFLOPS | 204.9 MFLOPS |
| Dot Product (multi-threaded scalar) | 246.2 MFLOPS | 435.5 MFLOPS | 361.5 MFLOPS |
| LU Decompression (single-threaded scalar) | 50.5 MFLOPS | 207.3 MFLOPS | 309.7 MFLOPS |
| LU Decompression (multi-threaded scalar) | 54.7 MFLOPS | 403.4 MFLOPS | 534.0 MFLOPS |
| Primality Test (single-threaded scalar) | 71.4 MFLOPS | 176.6 MFLOPS | 126.7 MFLOPS |
| Primality Test (multi-threaded scalar) | 69.2 MFLOPS | 316.8 MFLOPS | 194.5 MFLOPS |
| Sharpen Image (single-threaded scalar) | 1.51 Mpixels/s | 1.68 Mpixels/s | 482.1 Kpixels/s |
| Sharpen Image (multi-threaded scalar) | 1.52 Mpixels/s | 3.32 Mpixels/s | 858.9 Kpixels/s |
| Blur Image (single-threaded scalar) | 762.2 Kpixels/s | 664.4 Kpixels/s | 535.6 Kpixels/s |
| Blur Image (multi-threaded scalar) | 762.0 Kpixels/s | 1.31 Mpixels/s | 941.5 Kpixels/s |
The write sequential and sfdlib write memory tests in Geekbench confirm better RAM performance, but it's difficult to separate how much of this is due to memory technology and how much is attributable to the processor. At the end of the day, it really doesn't matter; what does is that throughput goes up.
Intel's Atom N450 still manages to remain top dog, despite it's 64-bit single-channel interface. The Atom only falls behind in the sfdlib allocate and write tests. However, the N450's 1.97 GB/s score in read sequential is about 6x higher than what we see in the iPad 2.
| Geekbench v2 (detailed results) | Apple iPad | Apple iPad 2 | Dell Mini 1012 |
|---|---|---|---|
| Memory Score | |||
| Read Sequential (single-threaded scalar) | 306 MB/s | 342.2 MB/s | 1.97 GB/s |
| Write Sequential (single-threaded scalar) | 849.1 MB/s | 1.02 GB/s | 1.32 GB/s |
| Sfdlib Allocate (single-threaded scalar) | 1.99 Mallocs/s | 1.83 Mallocs/s | 1.25 Mallocs/s |
| Sfdlib Write (single-threaded scalar) | 1.28 GB/s | 2.57 GB/s | 1.34 GB/s |
| Sfdlib Copy (single-threaded scalar) | 830.4 MB/s | 474.8 MB/s | 1.03 GB/s |
| Stream Score | |||
| Stream Copy (single-threaded scalar) | 465.5 MB/s | 449.9 MB/s | 1.18 GB/s |
| Stream Scale (single-threaded scalar) | 320.5 MB/s | 372.5 MB/s | 1.08 GB/s |
| Stream Add (single-threaded scalar) | 655.9 MB/s | 606.3 MB/s | 1.41 GB/s |
| Stream Triad (single-threaded scalar) | 427.4 MB/s | 426.6 MB/s | 1.11 GB/s |
Apple's A5 effectively underwent a three-part upgrade. Aside from its processor and memory, the iPad 2 now sports Imagination Technologies’ dual-core PowerVR SGX 543MP2. In comparison, the original iPad employs a single-core PowerVR SGX 535. That's the same GPU Intel used on its GMA 500, built into the Poulsbo series of System Controller Hubs for Atom.
| GPU System-on-Chip | PowerVR SGX 535 (Apple A4) | PowerVR SGX 543 (Apple A5) |
|---|---|---|
| SIMD | USSE | USSE2 |
| Pipelines | 2 | 4 |
| TMUs | 2 | 2 |
| Bus Width (in bits) | 64 | 64 |
| Triangle rate @ 200 MHz | 14 MTriangles/s | 35 MTriangles/s |
The SGX 543 includes four USSE2 (Universal Scalable Shader Engine 2.0) pipes. The SGX 535 only has two USSE pipes. This unified shader design is similar to what we've seen from competing graphics vendors for years, as it allows vertex and pixel shader code to share the same hardware. The idea is to get better performance, even if you’re rendering more of one type of shader. It’s not clear how these are second-generation shaders aside from their name, but Imagination Technologies states that the pipeline effectively delivers “twice the peak floating point and instruction throughput of the Series5 USSE.”
This isn't just about a revised SIMD architecture though. Apple also doubles the number of rendering pipelines again by placing two SGX 543 GPU cores on the A5 (the MP2 in its name represents that pair of GPU cores). This helps account for the iPad 2’s quadrupling of available GPU resources.
The GPU clock rate remains an unknown, so benchmarks remain the best way to determine effective performance. Unfortunately, it's difficult to measure real-world graphics capabilities in a meaningful way. There's no real equivalent to Fraps, and we're still a ways away from game developers including frame rate counters in their code. That’s why we turning to GLBenchmark 2.0, a synthetic OpenGL ES 2.0 metric that emphasizes texture performance. Think of it as the 3DMark of mobile devices.
| GLBenchmark 2.0 | Apple iPad | Apple iPad 2 | Motorola Xoom |
|---|---|---|---|
| Triangle Test (textured), Mtriangles/s | 8.6 | 29.0 | 15.3 |
| Triangle Test (textured, fragment lit), Mtriangles/s | 4.2 | 19.9 | 8.6 |
Like on a desktop, graphics rendering on a tablet begins with an application sending a GPU an array of vertices, vertex shaders, fragment shaders, and a bunch of other control information. The sum of this information is used to draw millions (or billions) of triangles that are used to assemble a larger 3D object. It's important to know the number of triangles that a GPU is capable of rendering because more triangles translates into greater graphics detail. GLBenchmark offers a glimpse into real-world triangle performance because it measures the triangle rate for an actual gaming scene. The results aren't that much of a surprise. At 29.0 Mtriangles/s, the second-generation iPad delivers 3x the performance of its predecessor. This means that game developers can conceivable increase geometric detail three-fold on the iPad 2 and get the same performance out of the original iPad.
The fragment lit test taxes texturing performance, with an additional focus on lighting. Thus, it's a more stressful benchmark. As the geometry becomes more complex, the iPad 2 demonstrates its improved handling of more detailed graphics workloads. It actually delivers about five times more performance than the original iPad.
| GLBenchmark 2.0 Frames per set duration | Apple iPad | Apple iPad 2 | Motorola Xoom |
|---|---|---|---|
| Egypt frames (frames) | 575 | 5075 | 1371 |
| Pro (frames) | 880 | 2897 | 1347 |
The performance of an actual graphics scene is easier to understand. When you look at this in terms of frames rendered in a set period of time, you're getting a lot more performance with the iPad 2. Conservatively, you're looking at least 3x more frames rendered according to the Pro test, and up to 8x more according to the Egypt test.
Comparing GPU Performance: Words of Caution
If you really want to go to the trouble of researching tablet-based graphics performance (there may be a few of you out there), bear in mind that potential won't always match up to the numbers you see in the real world. The form factor's constraints prevent vendors from pairing graphics hardware with the memory that'd best demonstrate its peak specifications, for example. Instead, you end up with the configuration that hits the performance profile needed, and nothing more.
On the desktop, a graphics card manufacturer has the freedom to balance performance between a GPU and its memory subsystem, altering data rate, memory bus width, and capacity to best exploit the processor's capabilities, whether they're bleeding-edge or decidedly mainstream. When you're dealing with smartphones and tablets, that's no longer the case. In order to cut back on power, minimize heat, or avoid monopolizing too much space on the PCB, engineers might tolerate a memory bottleneck in order to achieve other design goals. So, forget comparing individual and theoretical pieces of the graphics puzzle. Rather, focus on the end product's measurable performance.
| GLBenchmark 2.0 | Apple iPad | Apple iPad 2 | Motorola Xoom |
|---|---|---|---|
| Egypt with FSAA (frames) | 436 | 5057 | - |
| Pro with FSAA (frames) | 672 | 2851 | - |
| Egypt with FSAA Fixed Time (sec) | 825.6 | 65.0 | - |
| Pro with FSAA Fixed Time (sec) | 123.3 | 22.6 | - |
| Swap Buffer Test (frames) | 600 | 599 | 603 |
| Fill Test (texture fetch) ktexel/s | 170980 | 918551 | 129897 |
| Trigonometric Test (vertex weighted) kvertex/s | 1039 | 3326 | 2632 |
| Trigonometric Test (fragment weighted) kfragment/s | 1191 | 3512 | 4452 |
| Trigonometric test (balanced) kshader/s | 1259 | 3158 | 2543 |
| Exponential Test (vertex weighted) kvertex/s | 3130 | 3535 | 2628 |
| Exponential Test (fragment weighted) kfragment/s | 3774 | 11165 | 3003 |
| Exponential Test (balanced) kshader/s | 2043 | 11735 | 1656 |
| Common Test (vertex weighted) kvertex/s | 1524 | 3727 | 1973 |
| Common Test (fragment weighted) kfragment/s | 1634 | 3699 | 4451 |
| Common Test (balanced) kshader/s | 1065 | 4114 | 2530 |
| Geometric Test (Vertex Weighted) kvertex/s | 1949 | 3776 | 1316 |
| Geometric Test (Fragment Weighted) kfragment/s | 2081 | 6388 | 2888 |
| Geometric Test (Balanced) kshader/s | 1281 | 6181 | 1628 |
| For Loop Test (Vertex Weighted) kvertex/s | 1671 | 3860 | 1315 |
| For Loop Test (Fragment Weighted) kfragment/s | 1842 | 6237 | 7271 |
| For Loop Test (balanced) kshader/s | 1275 | 3718 | 3583 |
| Branching Test (vertex weighted) kvertex/s | 3906 | 3778 | 2633 |
| Branching Test (fragment weighted) kfragment/s | 6045 | 22557 | 3211 |
| Branching Test (balanced) kshader/s | 2106 | 11193 | 1493 |
| Array Test (uniform array access) kvertex/s | 2918 | 3658 | 3946 |
| Triangle Test (white) ktriangle/s | 9548 | 29957 | 12595 |
| Triangle Test (textured, vertex lit) ktriangle/s | 7058 | 21129 | 10520 |
There are two games specifically optimized to take advantage of the iPad 2's hardware. Infinity Blade is one of the most popular iPad games, and it's the first mobile game powered by Epic's third-generation Unreal Engine. This game comes straight from the company's studio, Chair Entertainment, which states:
One of the most popular gaming apps released to date, the ground-breaking Infinity Blade will be updated tomorrow with new optimizations specifically for iPad 2. Taking advantage of the processing power of iPad 2, Infinity Blade looks and plays better than ever and is the ultimate "show off your iPad 2's graphics prowess" app.
The difference in actual gameplay is much more significant than what a single screenshot can convey, but the iPad 2 clearly enjoys less aliasing, while we also see more complex geometry. Click on the images to see the full gallery for yourself. There is more detail in every scene, especially those with lots of lighting. We also noticed that gameplay is smoother on the iPad 2, whereas some scenes seemed to stutter on the original iPad.
Next up, Real Racing 2 HD is a continuation of a popular racing series from the Australian developer Firemint. According to the company:
For iPad 2, full-screen anti-aliasing, fully-modeled vehicle interiors visible through translucent windows, high-detail objects and surfaces and enhanced reflections
The difference is immediately noticeable when you open up the game. With the iPad 2, edges are fully anti-aliased, while reflections bounce off the surface of our 2010 Volvo C30 R-Design. Like Infinity Blade, gameplay is much smoother. There are no skipped frames or stutters.
Notice that the scenes are slightly different. Developers that optimize games specifically for the iPad 2 execute an additional code path. In the case of Firemint, the company has two different schemes for background detail. Only on the iPad 2 can we see flags above the race track's observation building.
There are a lot more differences in Real Racing 2 HD than Infinity Blade. Thanks to more powerful graphics processing, there are enhanced scenes on the iPad 2 that you don't see on the iPad.
Gaming on a PC is arguably more fun when you have a good display to match, but that also holds true for anything you do on a tablet. I don’t like to rely on subjective opinions in order to evaluate the quality of a screen, but there is almost no way to benchmark the IPS panel on Apple's iPad 2. On the desktop, we have programs like CalMan and ColorEyes to test a monitor’s performance, but these programs don’t work on mobile operating systems. Even if they did work, iOS doesn’t honor ICC profiles.
No program currently exists to test the performance of a tablet's LCD panel, which is why I spent the few weeks last month creating a custom program. The whole process is a little complex, but briefly, I’m measuring the color gamut at the display’s native settings (native gamma and white point) with a Spectracal NIST-certified i1Pro.


Even though mobile operating systems don't honor ICC color profiles, native color management does occur at the hardware level. When a GPU sends 10 different hues of blue to an LCD only capable of displaying three, the subpixels display the closest matching color. So in a way, smartphones and tablets behave like they’re using relative colorimetric rendering (for more information read our printer paper benchmarks).
Apple hasn’t really changed the technical performance of its iPad 2's IPS panel. The contrast ratio is better thanks to deeper blacks, but honestly, I’m actually a bit surprised at the low gamut volume. It’s about what you get out of a cheap TN-based LCD. Most people won’t complain because Apple sets the saturation too low, while increasing gamma and contrast. This makes color accuracy a bit harder to discern. However, if you’re a photographer who’s fussy about color, you’ll want to reconsider using the iPad 2 as a field tool. Compared to a notebook, you’re losing a lot of detail in blue shadows and midtones. This, in turn, causes some detail loss towards the magenta border in highlights as well.





Understand that these gamut measurements carry a few assumptions. First, we're disabling dynamic brightness because it doesn’t allow us to get an accurate (or reproducible) measurement of the display’s potential. Second, brightness is set to the highest value. If you don't use the same settings, your color gamut is going to look smaller than what we're showing here.
Apple continues to using a 1024x768 LCD display with 132 PPI (pixels per inch). So, the size of the individual RGB subpixels hasn't changed when we examine them under a microscope. Though, for some odd reason, the shape of an individual subpixel looks different. I suspect that Apple is using another manufacturer for the LCD panels in the iPad 2.
I found it easier to measure luminance uniformity in the portrait mode (home button on the left side). That's something to keep in mind if you're concerned with different viewing angles.
| Apple iPad | ||
|---|---|---|
| White Luminance cd/m^2 | ||
| 321.8539 | 333.5493 | 318.1339 |
| 342.3393 | 367.8701 | 335.3562 |
| 350.5158 | 333.3676 | 323.7054 |
| Black Luminance cd/m^2 | ||
| 0.5494 | 0.5354 | 0.5822 |
| 0.5617 | 0.6116 | 0.5861 |
| 0.6721 | 0.6600 | 0.5623 |


White and black luminance tend to be better towards the center. For some odd reason, though, only white luminance looks worse toward the edges. Meanwhile, black looks too bright near the center and center-bottom.
| Apple iPad 2 | ||
|---|---|---|
| White Luminance cd/m^2 | ||
| 330.0356 | 332.3039 | 358.7569 |
| 369.7601 | 363.3693 | 390.1944 |
| 385.2036 | 380.3892 | 380.3814 |
| Black Luminance cd/m^2 | ||
| 0.4470 | 0.5004 | 0.4247 |
| 0.5082 | 0.3999 | 0.4216 |
| 0.4921 | 0.4305 | 0.4184 |


The iPad 2 achieves better brightness, but uniformity looks skewed. White luminance, in particular, appears very different if you're viewing from the top and bottom. Thankfully, black luminance appears more uniform.
If you’ve already used the original iPad, nothing has changed. All of the same gestures apply: pinch, zoom, swipe, and scrolling.
Browser
Apple rolled out iOS 4.3 on March 9th, two days before the iPad 2's launch. While the interface didn't change, Safari claims big performance gains thanks the new Nitro JavaScript engine. You’ll still get this benefit from upgrading to iOS 4.3 on the original iPad, but the java experience is noticeably better on the iPad 2, since it has more CPU power to back up the engine.

I should point out that the new JavaScript engine also improves the original iPad's battery life, but this only applies when you're browsing websites that utilize JavaScript. If you tend to browse websites like Wikipedia (JavaScript-free), you're going to gain nothing in performance or battery life with the iOS 4.3 upgrade.
Multitasking
Multitasking in iOS
Manually Ejecting Programs from RAM
Multitasking is the same on the iPad 2; it hasn't changed. You have to double-tap on the home button to pull up the tabbing menu, and you still can’t multitask as smoothly as you can on a desktop. All applications run full-screen, so there’s no way to simultaneously manage multiple windows. For example, if someone messages me on Skype, I need to exit email and pull up the Skype program to respond. Apple needs to figure out how to better optimize the multitasking experience, because this is part of what makes us so productive on desktop PCs.
Until Apple addresses this interface issue, any other improvements wind up fairly iterative. The iPad 2 has more memory, for instance, and you do see the benefit of that upgrade when you switch between multiple programs.
In order to understand why, you need to realize that memory management in iOS works on the principle of first in, first out (FIFO). As with the desktop, opening more applications requires more memory. If the next application you open exceeds the amount of available memory, the operating system ejects the oldest program in memory to free up space, but since swap files aren’t used in iOS, ejected apps save their data to storage memory as soon as they move into the background. This affects the Web browsing experience because Safari doesn’t store Web pages locally. When the iPad runs low on memory, Safari can no longer store a page in RAM. Instead, it stores a preview of the page that refreshes when you return to Safari. On the original iPad, it was annoying to lose my place on a Web page because when I had to open other programs. With 512 MB of LP-DDR2, the iPad 2 no longer suffers this problem.
HDMI output
Apple neglected to include a digital video output on the original iPad, which is something that I constantly bemoan. Yes, you could output via component video, but multiple cables leads are a pain to deal with. In order for this to be painless, you really need a single-plug solution like HDMI, which Apple finally made possible on the iPad 2.
Of course, it isn't free. You have to buy this capability, and it's not cheap. Apple's Digital AV Adapter runs $39.
The adapter is simple, but I really think the ultimate in video output is wireless display technology like Intel's WiDi. In the meantime, Apple is covering the basics. The adapter has a single HDMI port for video output, along with a docking pass-through connector so you can charge the iPad 2 at the same time. Outputting video seems to drain the battery pretty fast. So, ideally, presentations made with your iPad 2 should be limited to two hours or so if you don't want to hook up the charger at the same time.
HDMI Output: 1920x1080 monitor
HDMI to DVI Output: 1920x1080 monitor
Video output isn't without its quirks. If you output via HDMI, native 1080p TVs and monitors display the image as an upscaled box in the center of the screen. If you use an HDMI-to-DVI cable, you'll see an upscaled image that takes up the total height of the screen. If you have a 1920x1200 screen, the image is correctly upscaled to fill the total height regardless of cable, but the 4:3 aspect ratio is preserved no matter what.
After a few days of mirroring the iPad 2's display, I decided that this isn't a perfect solution. I don't mind the upscaling, but I would prefer to have some sort of resolution control if I'm going to output to a larger screen. Apple also needs to fine-tune cloning because I don't need the iOS keyboard displayed on both screens. Ideally, it should only be visible on the iPad.
Playing video over HDMI is more refined. Regardless of the cable setup, you always get an image that preserves the aspect ratio of the original movie. According to Apple, media apps all have modes that are optimized for an external monitor. Netflix isn't listed, but this also applies to videos that you watch in that app.
| App | Notes |
|---|---|
| iPod | iPhone 4 |
| Videos | iPad and iPod touch (4th generation) |
| Safari | Video content on Web pages |
| Photos | Slideshow and video playback |
| YouTube | |
| Keynote | Available for iPad through the App Store |
Camera Quality
The front-facing and rear-facing cameras on the iPad 2 are really meant for FaceTime, which I unfortunately can’t test since no one else in the SoCal lab has the time to video conference (Ed.: So sue us for working!). No matter; the cameras are simply atrocious. The quality is good enough for Skype, but it pales in contrast to older smartphones that have 3+ megapixel sensors.
Apple narrows the competitive advantage of other tablets by adding cameras, but it does the bare minimum. Granted, nobody wants to even take a family photo with a big, awkward tablet, but at least exceed the capabilities of an old Blackberry Pearl. Yeesh.
Real-World Benchmarks
Early on we discovered how difficult it is to benchmark tablets.
Benchmarking responsiveness with a camera is the fastest approach. Of course, normal cameras won't cut it, since they only shoot at 29 FPS. That's unacceptable if you're trying to measure precise time differences. Going the stop-watch route is no better due to human-introduced errors. That's why I'm using a 1000 FPS high-speed camera to measure performance. Since, 1 frame = 1 millisecond, it’s possible to measure timings with a high degree of accuracy.
| Tom's Hardware's Real-World Benchmarks High Speed Camera | Startup Time (Cold Boot) | Input Lag | Launch Safari |
|---|---|---|---|
| iPad | 31.359 sec | 290 millisec | 717 millisec |
| iPad 2 | 25.977 sec | 235 millisec | 676 millisec |
Input lag is time it takes from pressing a key to the time it takes for it to appear as text on the screen. This tells you how fast the iPad is registering an action. Ideally you want low input lag so that you don't feel the tablet stuttering as you type or click on buttons.
Apple's original iPad has an input lag close to 300 milliseconds, which is noticeable if you have a tendency to type fast. According to research published by Clemson University, the average college student has a reaction time of 200 milliseconds to visual stimuli. The difference between 290 and 200 milliseconds is what you can actually "feel." If you type quickly, consider a 90 millisecond delay adding up per keystroke. Just Google "input lag iPad," and you'll see the how much of a pain this can be.
The iPad 2 has a more favorable result of 235 milliseconds, which means that input lag is nearly unnoticeable.
Battery Life
Testing a tablet’s battery life tends to be highly variable unless you control the entire experience from beginning to end. Cumulatively, touch gestures don’t have a great impact on battery life. The biggest factors are CPU/GPU processing, screen brightness, volume, and WiFi use. In order to accurately measure battery life, I coded a script that automatically plays MP3s at 50% volume while browsing different Wikipedia pages every 12 minutes. This benchmark is probably overkill, but it gives you an idea of a worse-case scenario.
| Battery Life Maximum Brightness, Dynamic Brightness Disabled, 50% Volume HH:MM | WiFi + MP3 | WiFi Off H.264 Playback |
|---|---|---|
| iPad | 5:36 | 8:01 |
| iPad 2 | 5:55 | 8:57 |
Based on the iFixit iPad 2 teardown, Apple's using the same battery in the iPad 2, so the improved battery life has more to do with efficient hardware.
Recharge Time
| Recharge Time AC Adapter HH:MM | to 90% | to 100% |
|---|---|---|
| iPad | 3:29 | 3:52 |
| iPad 2 | 3:01 | 4:02 |
Charging times are a double-edged sword. Ideally, you want a nice slow charge so that your battery lasts more than a few hundred cycles. Fast charge times keep you away from the wall socket longer, but in the long run they also cut down on the battery's health. Usually, the rate of charge starts to slow down somewhere in the 80% to 95% region, which is why the charging time from 0% to 10% is faster than 90% to 100%. This is where the iPad 2 shows its strength. It gets to 90% faster, but it eases up on the charging current above 90% to keep the battery healthy.
| Recharge Time USB Adapter HH:MM | to 90% | to 100% |
|---|---|---|
| iPad | 6:38 | 7:25 |
| iPad 2 | 6:23 | 7:24 |
If you're charging an iPad through a computer's USB port, expect to wait about 7 to 8 hours for a full charge.
Wireless Performance

It's wrong to look only at throughput to get a sense of network speed. Yes, the iPad 2 does slightly worse in throughput, but there are other factors that affect wireless performance. Latency, processing time, and the type of data being sent also effect the perceived "fastness" of a network connection.
Think of a phone call. Throughput is the audio quality. Latency is the amount of time from when you speak into the phone until the person on the other side hears you. And processing time is your brain mulling what the conversation itself. If we apply this to networking, throughput is the amount of data you can send over time, latency is the lag due to data transmission, while processing time is the overhead incurred by receiving the data.
Now consider that latency plus processing time equals response time. This is where the iPad 2 holds a clear advantage. Apple didn't change the 802.11a/b/g WiFi + Bluetooth 2.1 controller (Broadcom's BCM4329), but the A5's horsepower is significant enough that it reduces latency and processing time. So even if the throughput isn't great, the iPad 2 holds a commanding lead in response time that helps it load Web pages and download emails faster over WiFi.

In my opinion, the iPad 2's price is just as ridiculous as the original iPad. But that’s the nature of an Apple tablet. Remember that $499 for the iPad 2 is only the beginning. You also end up paying for a case, cradle, keyboard, HDMI adapter, and don’t forget the plethora of applications that you’ll feel compelled to buy. If you want a better idea of cost over time, don't be surprised to spend more on an iPad 2 than you might have otherwise spent on a mainstream notebook. Clearly, many folks don't know this or don't care.
| Apple iPad 2 Pricing | 16 GB | 32 GB | 64 GB |
|---|---|---|---|
| WiFi | $499 | $599 | $699 |
| AT&T 3G | $629 | $729 | $829 |
| Verizon 3G | $629 | $729 | $829 |
In a beautiful, perfect world, we'd like to see Apple drop the price of its iPad 2. Right now, the entry fee to own one is too high. Consider what you get. The WiFi version lacks proper GPS support. This is a major disappointment if you want to avoid 3G, but need help with directions. If you're a traveler, you really need some sort of cellular plan to get the most use out of your iPad 2 (and that puts you in another pricing bracket entirely).
I won't lie; the poor camera quality doesn't help matters. For a company that's talking up FaceTime and Photo Booth, it's drawing a clear line in the sand that tablets should have cameras. And yet, Apples shows up to that gun fight with a Deringer. The camera sensors are by no means impressive, which is disappointing given the importance Apple places on them. The company is only getting away with this because it has relatively mature software (Ed.: I'd argue it's only getting away with it because the previous generation had no camera at all).

Apple gets credit for setting the bar when it comes to UI. Last quarter, almost 20% of Apple's total revenue ($13.5 billion) came from iPad sales. In spite of more tablet competition, Apple is still doing relatively well because it demonstrated that the software/user experience is just as important (if not more important) as the hardware on which it runs. I think we can all agree that tablets aren't fully evolved, though. They don't really replace anything, and until we get to that point, tablets users are faced with "needing" a device that they can live without.
Depending on how you enjoy using technology, there can be other inconveniences associated with using a tablet in general. Enjoying one almost requires the right physical position. Sitting down with one in your lap feels mighty awkward after a while. Instead, it's best to recline and hold the iPad 2 against your thighs. Call us strange for taking this into consideration, but it goes to show that tablets aren't these uber-portable devices easy to use in transit.
Despite those issues, my biggest gripe is synergy. I don't want to keep track of the files that I have on my desktop, iPad, and cellphone. If you're batting two out of three for Apple (as in, you own a Macbook and iPad), this is even more important. When I'm done working on my desktop, I want to be able walk over to my iPad and have all my applications and data come with me. I don't want to have to worry about docking and synching every time I make a change to a document or add audio tracks. Unfortunately, there is nothing (yet) that enables this. Even the Dropbox App is an incomplete solution. iCloud is supposed to be the answer to all my synergy woes, but Apple's cloud service won't be available until iOS 5 rolls out in the fall. Until then, I still feel like I'm missing an important part of the tablet experience.
If you absolutely have to have the latest and greatest toys, regardless of whether they'll become an important part of your life, Apple's iPad 2 is the way to go. The company continues to set the standard and it's hard to have a serious discussion about tablets without including Apple, which is why we felt it was important to kick off our tablet coverage with this device, even though it's not exactly brand new. Make no mistake; there is plenty of competition. A significant number of competitors will pop up this year. So, hopefully, Apple uses this as an impetus for innovation. Tablets have the potential to be amazing, but I think it will take another generation or two before we're actually there.
























