My HTC One M8 dies in just about 12h-15h with screen on time of 3h-4h. It is connected to Wi-Fi network 90% of the time and I don't use a cellular data connection. Auto-Sync is on. Screen brightness is either 25% or 50% in direct sunlight. I am on stock 4.4.4 Rom software number 3.28.401.9
I...