Should you upgrade to an iPhone 4S?
iPhone 4: The iPhone 4's 1420mAh battery won’t get you much more than a day’s use before needing a top-up. Apple claims seven hours of talktime on its freshly-demoted number two phone.
iPhone 4S: That A5 chip will make the iPhone 4S more power-efficient but those apps will still take their toll on your battery. Apple has managed to bump up 3G call time from seven to eight hours and kept browsing time intact at six hours for 3G, or nine using Wi-Fi. We'd need to test out the standby time to see if this is really a killer upgrade, but if you could use an incremental boost in battery performance, the iPhone 4S licks it. Just.