If your Iphone 5 is not working – like not be able to hear when calling – with iOS 8.0.2 do this:
1. Backup your settings to iCloud
2. Erase the phone: Settings – General – Reset – Erase all Content and Settings
Swedish: Inställningar – Allmänt – Nollställ – Radera allt innehåll och inst.
3. When you start the Iphone again you log in with your Apple-ID and connect to your iCloud account
Done. I hope. 🙂
UPDATE 2014-10-23 – iOS 8.1 failing: Nothing above worked for me until I erased and re-installed iOS from iTunes.
(pic from softonic.com)