I'd be grateful if anyone can help me out with a problem I'm currently experiencing with my Galaxy S3.
The phone basically won't boot. It powers on fine, goes through the custom logo (for my network provider, Three) and then goes into the Samsung logo. There it stays, unable to boot.
What I think has caused this is that Three notified me of an over-the-air update to Android 4.3 from Android 4.1.2. I downloaded the update, and ran it, but I don't think it completed successfully and so the phone's firmware is probably now corrupt.
I sadly didn't take a backup and would really like to get the phone working again without losing text messages, apps, app data and so on.
I've looked at various options. I have the correct stock ROM/firmware for the phone (H3G version of 4.1.2). I could use Odin, or I could probably install Clockwork Recovery and use that. But I don't know exactly what I'm doing and in particular, how to keep my app data.