I've had my 4S for a year, not a bad little phone. In the last two weeks though, the battery has started acting very odd. Normally I run my phone during the day and plug it in while I sleep. No issues with a phone doing this in the 6 or so years I've had one.
My phone will go from 33% to 1% to off in about a minute flat. Then it crept to 40%, and has done it just two days ago at 53%. I'm wondering if anyone else has experienced this and if it's something I can fix? I thought it may be because the phone hasn't been backed up in a long time, but a bandmate has never backed his up and has no problems.
When it would die at 30%, two minutes plugged in and it would be back up to 35%.
When is the last time you did a full reboot?