The large, bright OLED screen on your iPhone is the single biggest drain on its battery. If you frequently check your phone, set it down on your desk, and wait for the screen to turn off on its own, you are wasting a significant amount of battery life every single day. By adjusting a feature called Auto-Lock, you can force your iPhone to automatically shut off its screen much faster when it detects that you are no longer actively using the device.
How to Change the Auto-Lock Settings
The Auto-Lock timer controls exactly how many seconds your iPhone waits in an idle state before it turns off the display and locks the device.
- Open the Settings app on your iPhone.
- Scroll down and tap on Display & Brightness.
- Scroll down to the bottom of the page and tap on Auto-Lock.
- You will see a list of time intervals ranging from 30 Seconds up to 5 Minutes (as well as a “Never” option, which should generally be avoided to prevent screen burn-in and rapid battery drain).
- Tap on 30 Seconds.
How Attention Aware Features Affect Auto-Lock
Setting the timer to 30 seconds ensures maximum battery savings, but you might worry that the screen will suddenly turn off while you are in the middle of reading a long article without touching the glass. Fortunately, Apple has built-in safeguards to prevent this.
If you own an iPhone with Face ID, your phone uses the TrueDepth camera system to track your eye contact. As long as you are physically looking at the screen, the iPhone will silently temporarily override the 30-second Auto-Lock timer. The moment you look away or put the phone down, the timer instantly engages, shutting the screen off exactly 30 seconds later.
If you want to ensure this tracking feature is active, go to Settings > Face ID & Passcode, and verify that the toggle for Attention Aware Features is turned on.