Android may finally be getting native support for Bluetooth battery indicators
However, don't get too excited just yet: the feature still appears to be in the planning stages. But even if it weren't, it still wouldn't make it to Android 8.0, the next major Android version, which has been finalized in terms of features since Developer Preview 3. And while XDA speculates the feature is slated for an eventual Android 8.1 release, we wouldn't get our hopes just yet. And that wouldn't matter for most users out there anyway, considering the abysmal adoption rate of new Android versions.
So for now, if you want to be able to easily read your battery level, you have a couple of options. The first one is an app called BatON, which has this feature, but is limited to only a few devices, and is reportedly quite buggy to boot. Or, you can install a custom ROM, though that is a difficult task for most users and poses some risks. And if neither of these solutions is good — well, there's little else you can do, unfortunately (besides buying a new device).
source: AOSP via XDA Developers
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