They Close out of Every App
Regularly closing out of your apps makes an intuitive kind of sense. After all, it probably helps your iPhone save on battery life and memory consumption, right? Truthfully, closing out of apps is a lot less helpful than it seems.
Newer iPhones do a great job of managing memory consumption, which means that most apps can be left open without straining your device. The same goes for battery life. And, in fact, closing out of apps may decrease your battery quicker, since reopening an app typically takes more energy than keeping it open.
There are exceptions, of course, but it’s generally best to keep frequently used apps open in the background.