iLounge posts some preliminary findings between the iPad Wi-fi and iPad 3G models. The 3G model was just released on Friday and includes 3G cellular data capabilities as well as GPS functionality.
Data services over 3G cellular tend to draw more power than on Wi-Fi alone. Apple's official specs show a 10% hit when using 3G vs. Wi-fi. Apple claims 10 hours of continous web usage on Wi-Fi, and 9 hours of usage on 3G with a single charge. iLounge's early tests show that these numbers seem reasonably accurate:
Our prior iPad with Wi-Fi battery tests found that Apple was generally at least a little conservative in its estimates; for instance, we put the Wi-Fi model through a web torture test with repeated 1-minute refreshes of a large, completely loaded page for 10 hours and 21 minutes on 50% brightness over 802.11n. Repeating the exact same test on the Wi-Fi + 3G model with 3G turned on and Wi-Fi turned off, the iPad achieved 8 hours and 38 minutes of continuous reloading and displaying -- 22 minutes shy of Apples estimate.
