I saw this a couple of weeks ago but now the App has been accepted by Apple and is available for download.
"Onavo’s app connects your iPhone to our cloud-based technology, dubbed the “magical shrinking machine”. It’s totally seamless – once you install it you can go back to using your phone as before. In the background, your data usage from all apps is compressed so that you get more bang for your buck, doubling and even tripling your data plan."
