I think you mean something like my attachment. You dont need an app for that the phone already tells you that, its built in. If you are running stock then go to settings then there should be a battery manager option go to that and from there you should be able to see how long its been unplugged and what has been using the battery. If not go to settings and scroll to the bottom to About Phone, there might be an option there for Battery use. The second part is most likely if you are running some ROM like RubiX or Liberty. If you dont know what that is then i reccommend you to read about what is rooting and what are ROMs. There are plenty of threads here and other places. Just use the search function.