On my old phone I had an issue with the proximity sensor and front facing camera. This led me to holding my phone backwards to take photos and being unable to hang up phone calls.
I think I put up with this for a year and a half.
I did end up figuring out the issue with the proximity sensor but opening up my phone to reconnect the camera module was too much effort for me.
The on/off/wake button on my phone broke off. I installed an app that would wake the phone automatically if the gyro sensors sensed it was taken out of the pocket, which worked around 60% of the time. I was a broke student at the time, so I dealt with that for a year or so before buying a new phone.