This is a mini battery monitor for your phone. It monitor the battery level in % temperature usage in °C or °F and voltage. It will always stay in the corner of your phone's screen. You can set the indicator to any corners of the screen customize the color and transparency of the indicator. Advanced notification support battery usage chart for 12 hours.

Pro version support auto-hide panel and other advanced features and it is ad-free. Free trial:
https://market.android.com/details?id=info.kfsoft.android.BatteryMonitor

★ Permissions ★

* Disk: Import and export the configuration files (Menu > Export / Import)
* Apps running in Background (App usage access - for android 6+):
a) system overlay compatibility: system didn't allow overlay on top of system overlays (e.g. system permission dialog) there will be "screen overlay detected" warning. If you give this access monitor automatically turn off itself and prevent such situation.
b)exclusion list function: it also require this permission so that it know what is running in the background and then hide the montior automatically for certain apps. The list is defined by users in Auto-hide section.