Don’t Waste Your Battery in Apps You Don’t Need
It goes without saying, but if you really want to make your battery last as long as possible, you need to stop using apps or games that are unnecessarily depleting it.
You don’t need to close them. As long as you don’t open them, your iPhone will basically shut them down so they don’t waste battery power. Be sure to also turn off Background App Refresh for these apps to prevent them from draining your iPhone’s battery behind the scenes.