1. WHOA! AppleCare can request to view your iOS device’s screen.
  2. Almost certainly a software issue, even though it happens on a fresh device only signed into Store.
  3. Escalated to Apple engineers.

Updating iOS in Recovery Mode didn’t help. Waiting for callback from AppleCare rep. Thirty minutes past scheduled call. Maybe she’ll be calling at 12:30 PST instead of MST?

Finally got some serious attention from Apple Support this morning. Working with a senior advisor to resolve my iPhone 7 Plus rear camera problem in third party apps. We’re starting with a Recovery Mode restore of iOS.