After a day with iOS5, I can honestly say I've experienced no major issues, at least compared to dozens of others I've read about on this forum. You MUST install by clicking 'RESTORE' not update and I highly recommend setting up as a new device, syncing contacts and mail, then installing Apps. Do not setup from your iOS4 backups.
- Only issue, after restart iPhone say Searching... but calls and SMS can me made/received. Airplane mode fixes this. No issues with the few dozen Apps I've used today, including Facebook. Battery life was slightly worse but I did use my phone more than usual because of the new OS. New Notifications rock!
- iCloud seems to be buggy, not backing up correctly and contacts don't sync properly so had to turn iCloud off and resync via iTunes for now..
- Custom ringtones sync and work fine
- Only issue, after restart iPhone say Searching... but calls and SMS can me made/received. Airplane mode fixes this. No issues with the few dozen Apps I've used today, including Facebook. Battery life was slightly worse but I did use my phone more than usual because of the new OS. New Notifications rock!
- iCloud seems to be buggy, not backing up correctly and contacts don't sync properly so had to turn iCloud off and resync via iTunes for now..
- Custom ringtones sync and work fine