I’m still getting used to leaving apps open in the background. I know iOS is very good at freezing things in the background, but are there any situations where you should force close an app instead of leaving it sleeping in the background? My wife is constantly shutting everything on her X, while I’ve been leaving all of my apps running. Battery life seems good, I’m just curious more than anything.
On Android if you open your phone and then power the screen off, the phone doesn’t sleep(doze) right away. Will an iPhone immediately go to “sleep” as soon as you power off the screen, or does the processor work in the background for a short time like on Android? Android has an app called “force doze” that you can use to force your phone to sleep immediately after shutting the screen off.
There are a few things you need to understand about iOS
Only a handful of apps (mostly the native apps) have special permission to run in the background. This would include Phone, Mail, Music, and some third part media apps. Some third party apps will continue to run in the background for a few minutes after the app is no longer in focus. i.e. if you see 20 apps in the task switcher it does not mean they are all running.
The "apps" you see in the task switcher are either:
- currently active
- have memory allocated but are not using cpu cycles (frozen state)
- represent more of a bookmark to an app that was once open.
When iOS needs memory it will go to the most idle app, kill it automatically and release the memory it was using. Of course an exception to this rule are system level apps (phone, messages, mail. etc).
Apple put the "close app" feature into iOS to force close an app that is misbehaving (frozen, not responding etc). Intentionally closing all apps is a bad habit because iOS uses unnecessary battery power to re-load all these apps back into memory again when a user needs them whereas it takes less battery power to keep the apps in a frozen state.
Hope this helps?
Edit: Forgot to add background app refresh. People seem to confuse this feature with an app running in the background. That is not how it works.
Background app refresh is a feature that Apple introduced in which iOS would learn when you used specific apps and have those apps automatically update in the background before you opened them. For example if the first thing you did at 8am was check your Facebook app than iOS would learn to update the Facebook app right before you opened it so you wouldn't have to refresh the app to see the latest updates.