How can I restore Camera app for f103

Solution
First try restarting the phone. (Turn it off and back on). That will often fix the problem. Should that not work, try using the phones external button for the camera. If it accesses the camera then the camera itself isn't the problem. If, however, even that won't access the camera, then the app may not be your problem. It may well be the camera itself.

If you can access the camera using the external button, then try going into "Settings" and then "Apps". Go to "All" and locate the camera app. Tap it and then tap "Enable". If it isn't listed under "All" then go to "Disabled" and see if it is listed there.
First try restarting the phone. (Turn it off and back on). That will often fix the problem. Should that not work, try using the phones external button for the camera. If it accesses the camera then the camera itself isn't the problem. If, however, even that won't access the camera, then the app may not be your problem. It may well be the camera itself.

If you can access the camera using the external button, then try going into "Settings" and then "Apps". Go to "All" and locate the camera app. Tap it and then tap "Enable". If it isn't listed under "All" then go to "Disabled" and see if it is listed there.
 
Solution