my s4 is almost 11 months old now. i was using it to listen to music in the gym when the screen suddenly went blank. i could sill hear/feel the vibrtion but nothing seems to appear on the screen. i've tried taking out the battery and putting it back again but that doesn't seem to be working. in the past few days i've noticed that the battery was running out fast and it took considerably longer time to charge it as well.
i have 2 questions:
1. is the a hardware or software issue?
2. any solutions?