4S charged up last night, sat in standby all night, battery was at 98% when I got up this morning: I'm not sure what the 16 minutes of usage was for... Since I mostly use my cell as a phone, and not an itty-bitty computer, I've shut down a number of options and accessories I only use when I want to use them. For example, a lot of places I go to have open Wi Fi, so unless I need the Network on for a reason of my choosing, I leave it off, just as I did with my previous Android phone. I found Siri really annoying, so I shut her down, too. I do check email and such on occasion when I am away from Wi Fi and when I do, I flick the Network on while I check and respond to emails, and then I shut Network back down. Anyway, this is my experience...your mileage, I am sure, will vary.