Samsung DeX
(Representational Image) Samsung DeX allows users to connectr their Galaxy S8/Galaxy S9 to a computer and use them as a trackpad.Samsung

As we inch closer to the launch of the first Android P Developer Preview, which is rumored to be released as early as mid-March, we are being introduced to more and more features that the next iteration of Android could bring along. And, the latest of them is something that will allow you to use your smartphone as a Bluetooth keyboard or mouse.

Now, this feature is something that we might have already seen before. Samsung's DeX dock allows the top-tier Samsung smartphones like the Galaxy S8 and the latest Galaxy S9 to be connected to a computer and used as a trackpad. Huawei also allows you to use some of its phones as a trackpad in its own PC mode. Microsoft, with its 'Continuum' mode had introduced a similar feature earlier.  But Android P could make the feature more mainstream by offering support for this feature on all future smartphones and also add the option to use the phone as a keyboard.

The way this feature will work on Android P phones is quite simple -- by using wireless Bluetooth technology. Android P will reportedly add support for a specialized Bluetooth profile called Bluetooth HID (Human Interface Device), which will allow users to turn their Android P-running smartphone into a Bluetooth keyboard or mouse.

A patch adding support for the Bluetooth HID was committed in 2016, but the functionality was disabled for future Android releases. However, folks at XDA Developers have now discovered two commits (basically, changes) in the Android Open Source Project (AOSP) for Android P which enable the Bluetooth HID device profile service.

Android P Bluetooth HID commit
Android P Bluetooth HID commit (screenshot)Android Open Source Project (AOSP)

Android, by default, does not support implementing Bluetooth HID, which means app developers cannot create apps utilizing the service to enable your smartphone to be used as a keyboard or mouse input device. However, the service has now been enabled (as per the new commits) and the APIs (Application Programming Interface) for developers have also been unhidden, meaning they can create apps that work on Bluetooth HID profile.

Having said that, there are some root-enabled apps currently available on Google Play Store that allow you to enable Bluetooth HID support and use you phones as a Bluetooth keyboard. However, native Bluetooth HID support in Android P would mean that all devices running the operating system can be used as input devices over Bluetooth without requiring rooting the device.

Using a phone as a trackpad might be useful to control workplace presentations, or as a media remote whenever there is better solution. This new feature is a step forward in expanding the inter-connectivity between the smartphone and other devices.  

Companies like Samsung and Huawei have already shown us how smartphones can be connected to a computer and used as a mobile workstation, and while this new Android P feature may not be as great as what these companies have to offer, it still won't be bound by an specific ecosystem (as in their case). 

Meanwhile, Android P is rumored to bring a host of changes and features on board. Among the biggest changes it will bring are support for iPhone-like notch on future Android smartphones, a revamped Material Design interface, and native Iris scanning support. Android P will also come with an enhanced call blocking feature that allows users to restrict certain types of calls.

Source: XDA Developers