This tweak simple will show alert/speak or both of them when you plug in/out your device to AC power or when you do activator action.
You can enable or disable what you want and to choose which way to get the information. When you do one of the actions this tweak will give you this information: How much battery you have, How much more % you need to get to 100%, And in how many hours and minutes your battery will be fully charged.
Now imagine you back to home after along day and you don’t have even power to check your battery or you just want to now how many time you need to charge your device.
So it will simple talk all the information that you need to now with out even look on the iPhone!