I now have the same problem with my s4. I was watching a movie on the android video player with the screen lock turned on. The phone shut itself down without warning and when I restarted it everything works bar touch. My first thought is that the screen lock function in Video Player is still on and im now unable to get back into the App to turn it off. Is this a possibility??
I have done all recovery mode options and what not. Im at a loss .
Any advice would be nice. Cheers