Don't upgrade to iOS 8.0.1 or you may experience “no service”
Many users are reporting on Twitter that it causes "No Service" and Touch ID to stop working. Do a search for iOS 8.0.1 on Twitter to confirm.
I had this issue and was able to fix it:
I did an OTA update (iPhone 6, AT&T) and experienced this issue. Touch ID wasn't working and "No Service" on the phone. I tried hard resets and resetting the SIM card, with no success.
I was able to fix the issue by downloading the iOS 8.0.1 ipsw from the developer site, then connecting the phone to iTunes, holding down option while clicking on update, and selecting the 8.0.1 ipsw. Phone redid update through iTunes (not OTA) and when it restarted, all was fixed.
Not sure how non-developers can get the .ipsw file.
Not sure how I would explain how to do this to, say, my mother. Hopefully there is a more sensible/easy fix that comes out soon.
Seems like it's hitting primarily iPhone 6 users. https://twitter.com/jsnell/status/514830848374214656
I just confirmed that re-applying the 8.0.1 ipsw through iTunes fixes the issue. Sounds like something is wrong with the OTA.
Upgraded, everything works just fine. T-Mobile.
Anyone with a problem iPhone 6/6+ on 8.0.1 want to dump the apple system log (asl) to see what's going on?
Just upgraded via iTunes (not OTA). No issues whatsoever. iPhone 6 64Gb AT&T.
Apple has now pulled 8.0.1 - There is no option to update on device any longer.
Confirmed here... iPhone 6 with AT&T -> no service.
Good job Apple, good job.
This isn't a problem on Android because you never get an update.
Never upgrade.