What to do if the iPhone camera does not work
Black screen instead of image in viewfinder
Check the lens. Make sure you don’t cover it with your finger or case, that nothing is stuck to it and that it is not dirty with anything.
Turn on Facetime. Perhaps the failure occurred in the regular camera application, in which case everything will be displayed correctly in other programs. If there is no black screen in Facetime or any other program with a camera, then you can exhale – the problem is with the software. And this means that it will probably be solved.
Close the camera application. And not just exit it, but find it in the task manager and close it with a swipe. Try checking the camera again – do it after completing each step.
Reboot your iPhone. You can turn the smartphone off and on, or use the emergency reboot. On iPhone 6S and earlier models, it is called up by a long press of the power button and “Home”, on iPhone 7 and 7 Plus – by a long press of the power button and volume down, on subsequent models – by successive pressing of the volume up and down keys, and then a long press of the button nutrition.
Update iOS. Go to "Settings" → "General" → "Software Update". If a new version of the operating system is available to you, upgrade.
Roll iPhone back to factory settings. Go to “Settings” → “General” → “Reset” → “Reset All Settings”.
You probably eliminated the problem in software at this stage. If all else fails, it is best to contact a service center.
The image is blurry
Make sure the lens is clean. Wipe it with microfiber to get rid of grease stains for sure. If you find dirt or debris under the glass, contact a service center.
Check the case. If you have an iPhone with optical stabilization (that is, 6s Plus or newer), the problem may be in conflict with a metal case or accessory with magnetic elements. Get rid of everything and test the camera again.
Resort to life hacks. Perhaps you just jerk your hand sharply when shooting. To make the descent smoother, use the volume button on the iPhone or EarPods to create a frame.
If the problem persists, contact a service center.
Flash does not work
Check lamp operation. Click on the flashlight in the Control Center. The same lamp is responsible for its light as for the flash. If it does not work, the problem is hardware – they will help in the service center.
Make sure the flash is on. Find the lightning icon in the camera’s regular application and set it to “On”.
If the flash still does not turn on, go through the third, fourth and fifth steps from the very first instruction and be prepared to visit the service center.
How to restart iPhone, put it into recovery mode or DFU
How to reset iPhone or iPad to factory settings
9 benefits of a triple smartphone camera