I'm having the same problem, Battery life 5 hours in StandBy... WiFi useless (I can't connect to any network) and the phone becomes really hot as well (all of this due to the 6.0.2 and 6.1)... I bought it in Movistar Co... today I'm going to claim a new one using the warranty, but previous conversation they said i need to leave the phone in "study" for 12 days. 12 days without phone! Hopefully I can get a new one coz this is really boring.
iOS 6.1 BATTERY FIX
Previous battery would last about 4-5 hours. Fix returned battery life to normal.
This has worked for at least 4 of my iPhones.
1. Completely update ALL apps on computer.
2. Completely update ALL apps on iPhone.
3. Physically connect iPhone to computer and synch. MAKE SURE TO MAKE A BACKUP.
- force a backup by right-clicking on the iPhone and select "Backup"
4. Transfer all apps from iPhone. Right click on iPhone in iTunes and select "Transfer Purchases".
5. Open iPhoto (or your photo app) and backup all of your photos.,
6. In iTunes, click "Restore to Factory Settings". It will take a little while.
7. When restored, you want to restore from the most recent backup.
That should do it.