We updated the older devices to iOS 6, took a luminance meter and set the screens of each device to 200 nits. We turned off Auto-Brightness and put each iDevice into Airplane mode. Lastly, we set the volume two clicks up from its lowest setting. With the same 120-minute video playing at fullscreen on repeat, we timed each device to see how long it took to drain the battery and power off.
Simply put, the iPhone 5 did not last as long as the iPhone 4S or 4. It lasted 8 hours and 21 minutes - about 6 percent less than the iPhone 4S and about 4 percent less than the iPhone 4. Compared to the two current iPads (which have much bigger batteries), the iPhone 5 lasted 27.5 percent less time than the iPad 2 and 17 percent less than the third generation iPad.
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