How does Background App Refresh work (in detail)?

As you just responded to an almost 4 year old post, it is not clear what information you are looking for. wjosten's post was about iOS 7; the current version is iOS 11.2, and things have changed considerably.

If you are asking specifically about Google Maps, by default it tracks your position all the time, so it can make suggestions without you asking, such as how long it will take to get home from wherever you are, or where to get lunch nearby. If you don't want this feature you can turn it off. Apple Maps has a similar function, as does Waze and other navigation apps.

While wjosten was correct that if you shut down an app it won't be able to do its background activities, however, if it has Notifications enabled it can be relaunched if it receives an update from a server. If it is it will not appear in the multitasking display, which is only apps that you have launched from the Home screen.

Nothing useful found

Mapping apps, like Google & Apple's app, by design, don't store data locally on your device. Thus, to use for navigation, background refresh needs to be on. To understand background refresh, read here:

http://support.apple.com/kb/ht4211

Be aware, this is also a huge battery drain, so unless needed, best to be left off.

If you force an app to quit by dragging it up from the multitasking display, it won't be able to do its background activities, such as tracking location or responding to VoIP calls, until you relaunch the app.

When you swich one app to another, iOS freezes it until you reopen it. It WON'T drain your battery even if is showing as an open app on multitasking. Some apps requires background refresh, so, even if they are "hidden", they are using battery.

But a common mistake is quit all of the open apps at the multitasking. It's an error because you will quit the program and clean your memory. When you open it again, the app will write all of the instructions in the RAM again, consuming so much more battery.

I think this will help.

Would be great to hear from Apple if this is true about quitting apps using more battery power due to using RAM when opening again???

The majority of people I speak to (include Apple reps in store) always say close all your apps at least once a week.

billybob1978 wrote:

Would be great to hear from Apple if this is true about quitting apps using more battery power due to using RAM when opening again???

The majority of people I speak to (include Apple reps in store) always say close all your apps at least once a week.

That's for a different reason. Not for battery life, but to allow iOS to perform "garbage collection" on RAM. As time goes on the RAM gets fragmented, with lots of small allocations. iOS can deal with that by moving apps around to open larger memory segments for new apps, but doing that slows down the phone. See this for the best discussion I have seen of battery life management: http://www.overthought.org/blog/2014/the-ultimate-guide-to-solving-ios-battery-d rain