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Software
The ZenFone 2 comes with Asus’ ZenUI running on top of Android 5.0. It’s a little heavy handed with both the design and preloaded software. It does help that performance is smooth and quick, the design generally follows Google’s Material Design guidelines, and some of the preloaded software can either be uninstalled or disabled. ZenUI also includes some handy features too such as launcher customizations, ZenMotion, one-handed mode, and various settings for both the casual and power user.
Google’s Material Design follows some general guidelines: icons are flat, colorful, and not skeuomorphic; generous use of white space to draw the eye toward certain elements; layers that create a sense of depth; and the use of animation to make the environment interactive. ZenUI follows these guidelines for the most part, however, Asus adds its own spin. By default the icons for system apps as well as app folders are all rounded squares, reminiscent of Apple’s iOS or Xiaomi’s MIUI. Pulling down the notification shade shows the usual details and pulling down again reveals quick settings. But where Google’s implementation shows a few simple options and a brightness slider, ZenUI shows a 4x4 grid of circular icons plus a brightness slider. There are enough options to bewilder the casual user; thankfully, the quick settings can be customized to the user’s liking.
The app drawer offers plenty of customizability. By default, app icons are arranged in a 4x4 grid, although there are several other options available ranging from 3x3 to 5x5. The default view mode is “Customized” which sorts all of the preloaded apps in alphabetical order first followed by downloaded apps ordered by date of installation. The “All” mode simply shows all of the installed apps in alphabetical order, while the “Downloaded” and “Frequent” modes provide options for showing only a subset of apps. You also have the ability to hide apps and group them into folders to reduce clutter. It also gives you the option to manually arrange the apps by dragging them around. Overall, the ZenUI app drawer is pretty flexible.
Asus’ custom launcher packs a plethora of options. Long pressing or swiping up on the home screen opens the “Manage Home” page which serves as a launchpad for several customization options. The included Themes app (shown above) provides an easy way for quickly changing the overall appearance of the UI, and digging through the options under “Preferences” reveals more settings for scrollable wallpaper, background transparency, folder grid size and style, icon label color, etc. These are the kind of in-depth UI tweaks usually found only in custom launchers, so it’s nice to see that Asus has included them here. ZenUI even adds a few extra buttons to the app switcher, including a shortcut to the app manager, screen pinning, and a very useful button to close all open apps.
The ZenFone 2 comes with several preinstalled apps and utilities that seem inspired by Asus’ PC heritage. For starters, in the display section of the Settings menu, Asus allows you to change the screen color mode between three different presets. There’s also a slider to manually adjust the screen color temperature and a “Customized” setting that also allows you to adjust hue and saturation. The basic file manager app grants access to local files and connects to several cloud storage providers, but it does not allow access to files below /sdcard. Auto-start Manager controls which apps are allowed to run in the background, potentially reducing RAM usage and extending battery life. And, in keeping with the PC theme, Asus includes the Clean Master and Dr. Safety apps, general utilities for managing RAM usage, cached files, and antivirus security.
Asus includes a few other options and features catering to both the casual and power user. Easy mode strips away the standard interface and replaces it with a simple 3x3 grid of app icons and enlarged text for the less tech savvy. Kid mode allows parents to restrict access to a group of select apps, block incoming calls, and set a time limit for device usage. For people looking to get work done, Asus includes a handy task manager that works with several of its other apps. After clearing items from the to-do list, you can plug in some headphones (which function as an antenna) and use the ZenFone 2 as an FM radio.
The ZenFone 2 comes with Asus’ ZenMotion, a suite of controls consisting of Touch Gesture, Motion Gesture, and a one-handed mode that streamline interactions with the large phone. Touch Gesture provides a variety of app shortcuts activated by drawing letters (see screenshot below) on the screen while in sleep mode. By default these shortcuts are assigned to system apps, however, they can be reassigned to any app the user wishes. This reviewer found it very useful to be able to draw the letter ‘Z’ and have the flashlight app quickly activate. Touch Gesture also includes double tap to wake and double tap to sleep the screen, immeasurably useful considering the awkward top-center placement of the power button. For the most part Touch Gesture works well provided you draw the letters large enough. However, occasionally the feature proved unresponsive; no amount of tapping or drawing produced any result. Only by hitting the power button to wake the screen then turning it off again would Touch Gesture be reactivated. It could be that during long periods of inactivity the CPU goes into a deep sleep mode where this feature gets deactivated.
Motion Gesture consists of a single option called “Shake Shake,” which takes a screenshot and adds it as a new task in the Do It Later task manager app. The shaking gesture is tricky to pull off; shaking too little or too much does nothing. The amount of shaking required is often enough to cause an app to switch between portrait and landscape modes, leading to possible screenshots in the wrong orientation. This feature also did not feel very responsive; there was often a gap of a second or two between the time the gesture was recognized and the time the screenshot was taken.
The ZenFone 2’s one-handed mode is quite useful for a phablet-sized device that sits between the LG G4 and Galaxy Note 4 in overall case size. This feature can be activated from the Quick Settings menu, but it’s far easier to enable using the quick trigger option which allows it to be activated or deactivated by a simple double tap of the home button. As mentioned previously, Asus’ implementation is similar to Samsung’s. Once activated, the screen shrinks and docks to one side of the display. A button at the top left restores the screen to its original size, while holding and dragging the top-right corner allows the screen to be resized as needed. The window can also be repositioned anywhere on the display. Virtual buttons for back, home, and recent apps appear at the bottom of the shrunken window. This feature works well for everything except games which still launch fullscreen. Exiting the game reverts back to the shrunken one-handed window as expected.
ZenUI performs well and looks decent. Asus adds its own visual flair and quite a few preloaded apps which might turn some people off, but many of these tweaks and apps are actually quite useful. Touch Gesture and the one-handed mode are welcome additions, especially for a phablet. It’s also nice to see so many options for customizing the UI, something missing from many OEM ROMs.