Definition
Background App Refresh is a smartphone operating system feature that lets apps you aren't currently using connect to the internet from time to time and download new content, weather, or feeds ahead of time. That's the name in iPhone (iOS) settings, and Android has a similar background data setting. Thanks to it, when you tap an app open, you can see the freshest content right away without waiting on a loading screen.
A Quiet Errand Runner Behind the Screen
When you switch to another app or go back to the home screen, the app you were just using slips behind the screen and goes into a paused state. It's a bit like sleep mode on a computer, and it saves battery.
But you've probably had this happen: you reopen a paused social media or news app, and the newest posts are already filled in, with no long loading bar. That's because your phone's operating system (the basic software that manages the device) gave the app permission to wake up briefly and run an errand to fetch new data from the internet.
Your phone also learns which apps you tend to open at which times of day. It looks at your usage patterns and your Wi-Fi connection, and refreshes data ahead of time only at the best moments, without wasting battery.
A Little More Precisely: It's Not the Same as Push Notifications
Many people worry that if they turn off Background App Refresh, they'll miss messages from friends or delivery app alerts. But the notifications that pop up on your screen and this feature work in different ways. (One exception: a silent push, which quietly wakes an app so it can fetch content ahead of time, only works when this setting is on.)
A push notification is like a signal light. An outside server knocks on your phone's door and says, "You have a new message!" Background App Refresh is the other way around. The app grabs a shopping basket, heads out to the internet, and checks, "Is there any new photo or post to bring back?"
To be a little more precise, even if you turn this feature off completely, push notifications still arrive as usual. The only difference is that when you tap a notification and open the app, there may be a short wait while the actual photos or conversation download from the server.
Smart Ways to Save Battery
When apps you can't see keep talking to the internet in the background, your phone's processor and wireless chip have to keep working. That slowly drains your battery and data.
If you allow this feature for every app on your phone, your battery can drain fast even when the phone just sits in your pocket. So it pays to turn it on only for the apps you really use often and need to check right away.
For example, keep it on for apps like weather, maps, and live stock prices, where you want the latest info at once. Turn it off for shopping or game apps you open only a few times a month. The operating system already limits how often refreshes happen, so the effect varies from app to app. Still, switching it off for apps you don't need can help cut battery and data use.
Common misconceptions
If you turn off Background App Refresh, you won't get WhatsApp or text message notifications.
Push notifications that pop up on your screen and Background App Refresh are separate features. With the feature off, notifications still arrive normally. The only difference is a short loading wait when you open the app to fetch the latest content.
Where you meet it
You open a weather app and the current temperature and air quality are already on the screen, with no loading.
You open a social media app and your friends' new posts are already lined up at the top of the screen.
In one sentence
This feature downloads fresh data before you open an app, so you skip the loading wait. To save battery, it's best to turn it on only for the apps that need it.