iPhone 4S restarting 20x a day since iOS 8.4.1 was installed I have an iPhone 4S it is restarting 20x a day since iOS 8.4.1 was installed.  I have the Apple Music service turned on. I am going to turn it off because it keeps causing problems with playing iTunes, but I wonder if anyone else has experienced these restarts, and if so, what configuration options cause it or make it go away.  

If it turns out turning off Apple Music solves this issue, I'll post that as an answer. Any other idea?

Update: The backup/reset/restore suggested in the answer below also cleared up 20 gb of JUNK/crap in the "Other" category from my iPhone:
If this popped up right after an OS upgrade than I would wipe the phone and restore from backup:


Backup phone in iTunes
In Settings > General > Reset: erase all content and settings
Once that is done restore from backup


My guess is that a file got damaged during the upgrade and restoring it may fix it.