While no feature allows you to close all your opened apps at the same time, you can close several apps simultaneously on your iPhone or iPad. All you need to do is access the App Switcher as you normally would (which we'll explain below). Then, use multiple fingers to swipe multiple apps off the screen at once.
It takes a lot of power to close an app, it takes even more to open it up again. Doing this will reduce battery life, you're better off leaving them open, iOS has very good RAM management so most will stay open just fine.
Stop Closing Apps on Your iPhone Constantly
You shouldn't swipe away all the apps in the App Switcher. Doing so prevents iOS from running as intended, wastes power by forcing apps to reload for no reason, and makes switching between apps less convenient.
From the Home Screen, swipe up from the bottom of the screen and pause in the middle of the screen. Swipe right or left to find the app that you want to close. Swipe up on the app's preview to close the app.
Close all apps: Swipe up from the bottom, hold, then let go. Swipe from left to right. On the left, tap Clear all. Close all apps on Android Go: Swipe up from the bottom, hold, and let go.
You can also use the Alt + F4 keyboard shortcut to close an app or program on Windows.
Open the App Switcher by swiping up from the bottom of the screen to just below the center, holding for a second, and letting go. You'll see your open apps displayed as a row of screenshots overlapping each other. Swipe right or left through your apps and swipe up on the app you want to close.
It's especially important to avoid exposing your device to ambient temperatures higher than 95° F (35° C), which can permanently damage battery capacity. That is, your battery won't power your device as long on a given charge. Charging the device in high ambient temperatures can damage it further.
Avoid extreme ambient temperatures.
Charging the device in high ambient temperatures can damage it further. Software may limit charging above 80% when the recommended battery temperatures are exceeded. Even storing a battery in a hot environment can damage it irreversibly.
The most fruitful battery life gains were found when switching from light mode at full brightness to dark mode. In the Purdue study (via Android Authority), researchers looked at dark mode power usage from six different applications.
Clear cache in Safari
Open Settings > General. Tap iPhone Storage and select Safari from the list of apps. Tap Website Data to view a breakdown of your data by website. Tap Remove All Website Data at the bottom of the screen, and confirm with Remove Now.
The iPhone 13 has built-in tools to automatically manage background apps so that they aren't taking up unnecessary battery or memory resources. It was designed with the intent of running multiple apps at once, so going through and manually closing them all the time is mostly redundant.
Closing Android Apps Doesn't Increase Your Phone's Battery Life. It's natural to think that background apps constantly use up your phone's battery. However, those apps are not the cause of your battery drainage, and closing them frequently will not increase your phone's battery life.