Hi everyone, I just received my iPhone 4s factory unlocked today and activated it on Metro PCS. The phone was used and I want to know if the battery life is normal. I wanted to calibrate the phone so I charged it full and then let it die. Usage time: 6 hrs 40 min stand by: 7hr 21 min @ 7% battery. Also, it died at 4% which I found strange, is this normal? Thank you.