To resolve frozen app switcher issue, i hard reset my iPhone. After that, I find the camera app is gone, and camera in messages app does not work either. Restarting and hard reset does not solve my problem. Anyone has Idea to bring it back? PS: running iOS 10 DP 2 Update: problem solved. I turned off camera in Restrictions setting, alongside FaceTime app so they were gone from home screen. Don't know why I turned them off in the first place.