iPhone: When should the network activity indicator be used

Question

I have just started including networking functionality into my apps. I know that you should use the network activity indicator when the user is actively waiting for something, but what about if it was just a subtle background communication with the server (in my case, just to update a value) - is it still good practice to let the user know that your app is connecting to the internet?

This is something I find interesting about the iOS platform - that it lets its developers tell the users whether or not the internet is being used.

UPDATE: In this specific case I'm downloading a text file which is 4 chars long!!

Answer 1

As usual a look into the HIG and the documentation is useful.

This is what apple says about the network activity indicator.

Guidelines

Display the network activity indicator to provide feedback when your application accesses the network for more than a couple of seconds. If the operation finishes sooner than that, you don’t have to show the network activity indicator, because the indicator would be likely to disappear before users notice its presence.

Answer 2

Apple's own iWork apps don't use the network activity indicator, even though they are constantly uploading the changes to the server.

I think that if the user is clearly aware that the app accesses the internet (i.e. they explicitly allowed it), there is no need to show the indicator for every small network operation. It is intended for indicating that a larger amount (>100kb) of data is being uploaded/downloaded, and keeping the user informed, that the app is still working.

If you just think of iCloud as an example, I think it would be very annoying to continuously see the network activity indicator spinning.