

Low Power Mode is automatically turned off when your iPhone or iPad is charged to 80% or higher. You'll know that Low Power Mode is on if the battery icon at the top-right of your screen is yellow instead of white or red. EDIT2: for those saying this is a 'myth', the following is from Samsung website and not an obscure android east-Asian tech news website.

Your iPhone or iPad will automatically lock after 30 seconds if you're not actively using it and iCloud Photos is temporarily paused. EDIT: I started using Battery Charge Notifier by Utopi (no ads, no in-app purchase). When Low Power Mode is turned on, features like email fetch, background app refresh, automatic downloads, and some visual effects will be reduced or affected.

If you choose to ignore the message, you'll get another prompt to turn on Low Power Mode at 10% battery. Typically, your device will automatically prompt you to turn on Low Power Mode when your battery level dips below 20%. Low Power Mode saves battery life by reducing the amount of power your iPhone or iPad uses. When you're low on battery and can't charge your iPhone or iPad right away, Low Power Mode is a helpful tool to maximize what battery you have left and keep your device running.
