Can one continuously poll the iphone for GPS coordinates?

The iPhone app I'm thinking of developing needs to be able to report the GPS coordinates to a backend service at regular intervals. It's my understanding that the iPhone currently does not support background applications, which means that there's no way for me to leave an app running in the back and sending coordinates to a server.

What's a reasonable workaround? Since push notifications are available on the iPhone, can the server actually pull the phone for any kind of dat开发者_JAVA百科a? While not ideal, that would still update the backend with the necessary information.

Thanks!

iOS 4 allows apps to access some of the GPS functionality in it's limited multi-tasking, back-grounded state. See here.

EDIT

As per this SO question, also see the API for getting updates on significant location changes.

And how to do it in the background on this SO question.