iOS processes while in background

Question

Is it possible to interface with a webservice (or, for what matter, do any scheduled local or remote activity) while the app is in background?

I know that you can receive remote pushes or schedule local alerts, but I wonder if I can periodically send my GPS position to a webservice even if the app is not in foreground.

Answer 1

You can make sporadic network calls while you are running in the background if you are a location-based app with proper permissions. You need to make sure you are running a background task properly. FYI, there are a number of applications in the app store that do this.

Answer 2

I have been thinking about this myself in an attempt to impress my boss with an iPhone/iPad App that accesses our Web Service.

If the Web Service takes a non-trivial amount of time to process a request then there is absolutely no guarantee that the App won't be interrupted and stopped, therefore making it useless for any business-level tool. The only Apps that are allowed to run for extended periods in the background are a select set that use certain frameworks (music players, etc.).

I concluded that the only way of doing it is to introduce a middle tier that performs and waits for the response from the actual Web Service and provides an interface that the iOS App can poll or be pushed to in order to allow it to sleep/die whenever iOS thinks it should.