If you put your iPhone on low power, but are concerned about the impact of this, here is everything you need to know. Is it okay to leave your Apple iPhone on low power mode all day? Responding, one person on the Apple page wrote: "Low Power Mode changes how your iPhone works to a certain extent." They added: "Low Power Mode automatically turns off 'when the device is sufficiently charged.' Recommended Reading:What should I do if my iPhone battery is rubbish after an Apple update?