It is really simple. The newer generation of phone are built with multi-core processors, more RAM, more storage, faster GPUs and CPUs. Ubuntu for Android enables such handsets to run Ubuntu on their handset alongside with Android OS.
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So the idea is a simple one. Since both the Android and Ubuntu share the same Linux kernel, so they can exist simultaneously in a same handheld device. So the handheld device is Android for the phone experience and Ubuntu when docked.When docked the user still have access to the phone’s functions when it’s docked so the user can do task of phone such as making and receiving calls even when docked.This results in one address book, one set of bookmarks, one place for text messages and one inbox for mail. So you would get a device which can operate both as phone and PC.
The hardware requirements are straightforward and, with a broad range of ARM and x86 hardware supported, it can realistically be added to phones already in development.Of course, your phone needs the docking capability and hardware support for HDMI and USB. But that’s standard for high-end models in the current generation of devices in development.