PokeBatterySave is an application for ROOT users to lower power consumption while playing Pokémon™ GO. One of the things it does is turning on Android's Battery Saver ON when the game is in the foreground (and other lower level changes, which are the secret sauce™). It also turns the Location mode to Battery Saving if you choose the Super saver setting. When the game leaves the foreground everything is restored to System defaults, including disabling the system Battery Saver.
You wanna play for the longest time Like no one ever was To have battery life is my real test To charge it is my cause
I will find all the outlets To charge far and wide Each downtime to understand The lack of battery that's inside
Battery, gotta charge it all You need PokeBatterySaver I know it's your destiny
More battery, more play time, more chance to catch them all.
Bonus: this'll also work with Ingress since it's also make by Niantic.