My iphone has been dying at 50-60% lately and the other day it died at around 80%! I have tried upgrading to the latest FW but this doesn't seem to have helped. The only thing I can think is to replace the battery but this is a last resort. Is it worth trying a DFU install? Or is there someone to completely wipe the iPhone and start over, thinking it may be an issue with the software as it dies at different percentages each time. My phone is Jailbroken also but I can easily reverse this if possible. Also is there a way to recondition the battery?