Do you have code snippet? Or full error message?
Let me take a guess. In your code where you access the camera, you should check the camera permission before you just use it. I think that's where the problem would be. For how to do that, check [question]: Detect permission of camera in iOS But I might be wrong. need more info. And I also think you didn't correctly set your plist, you need to add following attributes in you plist.
Photo :
Key: Privacy - Photo Library Usage Description
Value: $(PRODUCT_NAME) photo use
Microphone :
Key: Privacy - Microphone Usage Description
Value: $(PRODUCT_NAME) microphone use
Camera :
Key: Privacy - Camera Usage Description
Value: $(PRODUCT_NAME) camera use
And one more thing, when you encounter a crash or any weird behavior, look for its reason, look into its log, look deeply into its err message. search for the error code, put exception breakpoints
to find exactly where the crash happens, etc. And then, post questions related to how you cannot solve those materials/experiments you went through. That is more effective than just agonize yourself over the app behavior.