When an iOS application goes to the background, are lengthy tasks paused?

Question

Yes, I know if I wish my app to be responsive to users\' multitasking actions, such as switch to another app, I should deal with

- (void)applicationWillResi         


        

Answer 1

Like mentioned above, there are a few cases where your app runs in the background and apple can allow or deny depending on what you are doing.

https://developer.apple.com/library/ios/documentation/iphone/conceptual/iphoneosprogrammingguide/ManagingYourApplicationsFlow/ManagingYourApplicationsFlow.html

More importantly if you do fit into one of these categories your app refresh rate is determined by an apple algorithm that takes into consideration your app usage on that device vs other apps. If your app is used more often then it gets more background time allotted. This is just one variable but you get the idea that background time allocation varies app to app and not under your control.