We spent most of the weekend putting the iPhone 3G's battery life (and to a lesser extent, MobileMe implementation) to the test, and we've got far more encouraging results to report back than we had on day one. Pretty much everything we've found thus far jibes with Apple's claims, if not exceeds them. (Our video results early on skewed low because we had mistakenly left on push and fetch data, which dropped the battery life by almost 25%. After re-testing, they're back up to spec.)
All tested with 3G on, WiFi on (not connected), Bluetooth off, no data fetching enabled (unless specified otherwise). Media tested with stock headphones, medium volume, and medium screen brightness, auto-brightness disabled.
- Music (continuous playback, large library, occasionally turning on screen): 31h 23m
- Video (continuous playback, no push/fetch data): 7h 5m
- Video (continuous playback, with push and 15 minute fetch data): 5h 24m
- Daily data use (browsing, email, and GPS / maps): ~6h 30m