I have a Galaxy Note ll I was having battery issues where once it reached about 30% it would die in twenty minutes. I mentioned this to someone and he rooted my phone for me and did some things to "fix it", but now my phone is completely messed up. After he fixed it he told me to charge it to 100%, use this battery calibration app, let it completely run out of battery, then charge it to 100% after it died while it was still off. I did this, restarted my phone and used it like normal, then a few hours later my phone started freezing up, the battery jumped from 50% all the way to 17% percent and kept locking up. I have no idea what to do.