Hello! There's a little thing to do that gives you up to 50% of extra battery (according to my tests it's about 30-40% more, on average). Just disable cellular data while using a Wi-Fi network. Cellular data is used by your phone for MMSs only (which no one uses), so everything will keep working fine. CALLS OR MESSAGES ARE NOT AFFECTED. Disabling the 3G/4G antenna while using Wi-Fi will dramatically improve your battery life, since this antenna is uselessly used while you're connected to a wifi network (iOS doesn't automatically disable it). We need a toggle in the control center for cellular data. Why doesn't Apple put it? It would be one of the most useful things that the history of iOS remembers. I noticed that a lot of people on this forum deny that turning cellular data off can improve your battery life. Well... they didn't test it for sure, since it's a huge improvement. Let me know. PS: Obviously, disable the 4G or the 3G antenna, too.