"Warning Camera Failed" every time I open the camera app

I have the HTC One. Great phone as is the S4. But when you mass produce things there are going to be problems. The HTC has dead pixels etc. I love the phone and haven't had any problems but plenty of people have had problems. Plus they both have just been released recently so there are bound to be bugs. I don't know why you picked your phone but I would maybe give that phone another shot.