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Bloated social networking apps are your issue, not the phone. Facebook is a resource hog that makes all other resource hogs look like amateurs.

Also echoing the sentiment, actually getting out a bit more rather than interacting behind the screen solves the "issue" 100%.
 


Privacy location services- switch off share location, turn off location for those apps that do not need it. Also background app refresh. Turning off airdrop & siri if you do not use. Turn off auto brightness & adjust manually. Reduce motion in accessibility.
 
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