Android manufacturers and custom ROM makers usually put in APIs to track Bluetooth accessories’ battery levels. Unfortunately, these indicators are fairly crude, mostly only appearing on the notification bar and not in a settings page. Even though third-party apps can take advantage of reporting data through a Bluetooth SIG standards, they tend to be hit-and-miss.
Well, it looks like Google is finally going to take on this tricky task — really, when has working out background tasks through Bluetooth ever been an easy thing? — with some new APIs to retrieve and display Bluetooth accessory battery levels and their state changes. Spotted by XDA-Developers, a couple of commitments to the Android Open Source Project gerrit show that specific battery percentage numbers could also be displayed. Subordinate standards from Plantronics and Apple as well as Bluetooth Low Energy may also be supported somehow.