iOS 10 Photo Focus Glitch

Hey.

Had 6s for a few month already with no problems. Few days ago I updated it to iOS 10. Today I used camera first time after update and found out that, after I launched default camera app, focus hanged. I mean the app itself is just fine. I can switch modes. After I switch to video, it's okay again. I reboot, put phone on table and after few hours launch app again: same thing, focus hangs. As if camera hangs on start trying to focus in blurry image. If I move camera, picture changes a bit, but still, not focusing. And strange thing is that when I switch to front camera, it hangs along main camera as well. After switching mode, it's okay again.

The main question is that a bug in iOS 10? I can't believe hardware issue can appear like that out of the blue and affect both cameras in one mode only...