Can someone help me understand how iphone battery .... works?? I have noticed that some days... the phone has EXCEPTIONAL battery and other days i have drain for no apparent reason... Let me explain: Before I start though, please keep in mind that both situations I explain further down are with completely charged phone, with no apps in the background and the EXACT same settings. So here it is: On the one day, after a full charge, I leave the phone doing nothing (standby) with everything on (3G, Wifi, LTE, location on etc etc) and the phone after 6 hours loses only 1-2% of battery and is at 99-98% charge. PERFECT. The next day, I am doing the EXACT same thing. Charge the phone, everything ON as the last day, leave the phone in standby for 6 hours doing absolutely nothing, and ... BAM! Battery is at 85%.... I mean... why? What is happening that is so different from one day to the other? I look at my usage at the example of 85% day and I see a lot of "used time" when in fact i havent even touched the phone. And as I said background apps are all closed. Why is the phone battery performance incosistent from one day to the other? Are you experiencing something similar?