Sad to report, I'm having the same issue. My phone hasn't left the charger today, and I'm at 1% battery. Only app I've randomly used is the calculator. The phone will charge when it's powered off, turn it back on and zoom! goes the charge.Top half of my phone is hot, like the above comments have stated, too.

In the time it's taken me to write this, my phone is now at 0%. I haven't touched it!!!