With PowerSaver you can perform actions like turning of wi-fi, turning on airplane, lower Brightness, Respring, Reboot and many more when the battery reaches a specific percentage. For example you can set when battery reaches 3% to respring or when it reaches 10% to turn off wi-fi or when it reaches 99% to increase brightness or when it reaches 57% to show the lock screen.
Perform Actions when Battery Reaches a Specific Percentage. Can be any % you want like 99% or 1% or 52% or 39% or 17%.
You can set upto 14 battery % Alarms.
Don’t Worry EnergySaver itself does not take any extra battery itself ;)
No icons are added to the homescreen. Configure PowerSaver from Settings app.