file size limit for App Store downloads over wifi iPhone

I just gifted my friend a navigation app that is 1.4 Gb in size. Unbeknown to me, her iPhone is not tethered to a computer and therefore she only downloads apps directly to the phone via wifi. Is it possible to download a file of this size directly to the phone? So far the app has said Loading... for 3 hrs with no movement in the status bar. If there is a limit I would have expected the phone to disallow the process from even beginning.
Any thoughts on how to get this app downloaded would be greatly appreciated.
iPhone 4 iOS 4