[Badger5098]

After the last update of IOS my iPhone 6 began to go to a black screen when I select an app.

It's not the same app all the time and I can get the app if I hit the home button and select the app again. Sometimes it's an Apple app (eg, calendar) and often it's a third party (eg CNBC). Frustrating.

Resetting (power and home buttons together) the phone hasn't helped. I'm open to other suggestions.

[Just_Me_D]

Connect the device to your computer and then have iTunes reinstall a fresh copy of iOS via the restore option. That's what I'd do. Yes, it's an inconvenience, but it could also solve your problem, in my opinion.