Deep Sleep Battery Saver Pro allows for deep sleeping a device while the screen is off in order to save battery power. It costs $3.28 and includes in app purchases.
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Pro 5 profiles for different performance levels
There are 5 preconfigured profiles that allow the user to choose a setting that saves a certain level of battery.
Pro Cloud sync
For those that use multiple devices there is a cloud sync feature that allows the saving of settings and custom profiles. This way there is no need for setup on a new or different device.