I ran my iPhone 4s's battery down to 5% and I got around 5 hr of usage time and around 13 hrs of standby time since the last full charge. Out of the 5hrs of usage time, about 1 hr was used for calling, and the rest for emails, browsing the internet, and music. No videos or 3D games. Is this normal or is something wrong with my battery? What's a normal range of battery usage time? This is my first iPhone and I've had it for only 2 weeks. I don't have anything to compare it with, other than my iPod touch 2nd gen, which seems to have better battery life even though it's 2 years old. Also, about 30 min into the call, I noticed my phone became warm. Is this OK?