Apple says that battery life on the iPhone 4S should be comparable to the iPhone 4, even though the smartphone features a dual-core processor with two times the speed and seven times the graphics performance of the previous model. The company also expects the iPhone 4S to delivering an extra hour of talk time per charge over 3G than its predecessor.
It comes at the cost of one less hour of Internet usage over Wi-Fi (10% less), and 33% less standby time. These sound like big changes, especially in standby time, but over the last few days I didn't notice much of a difference in battery performance compared to the iPhone 4.
