So the main cause of the battery drain is Facebook. Follow this article to fix the battery drain issue. You need to turn Location History off to stop Facebook from monitoring your location when you’re not interacting with the app which was actually killing your iPhone battery.
How to disable Location History on Facebook
Step 1: Launch Facebook’s official iOS app on your iPhone.
Step 2: Tap More in the tab bar alongside the bottom.
Step 3: Now Tap the Nearby Friends section.
IMPORTANT: If you don’t see this option, their neither Nearby Friends nor Location History are live in your area yet.
Step 4: Tap the gear icon.
Step 5: Choose Location Settings.
Step 6: Tap to turn Location History on or off.
NEXT STEP: After disabling Location History inside the app, you also should change location access for Facebook’s app on your iPhone from ‘Always’ or ‘While Using the App’ to ‘Never’, as outlined further below.
How to change iPhone location access settings for Facebook
Step 1: Launch Settings on your iPhone.
Step 2: Tap on Privacy → Location Services → Facebook.
Step 3: Tap on ‘Never,’ or choose ‘While Using the App’.
‘Never’ vs. ‘While Using the App’
Choosing ‘Never’ is a sure-fire solution to the problem: this will stop all location tracking for the app and also prevent certain location-based features from working. For example, you won’t be able to add location to your posts, use Nearby Friends and Nearby Places, tag posts with location and so forth.
As a workaround, temporarily adjust location access for Facebook to ‘While Using the App’ in iOS Settings when using these features, and revert to ‘Never’ when finished.
Choosing ‘While Using the App’ allows Facebook to access your location when the app or its features are visible on the screen. “Facebook uses this to make some features work, help people find places and more,” says the prompt.
Keep in mind that Facebook has been found to employ dirty tricks to keep its app awake and running in the background on your iPhone, even when you’re not using it.
Last suggestion from me: Go with the ‘Never’ option to be 100 percent sure. This will extend your daly iPhone battery life.
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