It used to support microsoft exchange for free users, which allows you to get push notifications by using native mail app on iphone. However, in dec 2012, google decided to take it off. Now only IMAP is supported for free users (ie. no push on native mail app).
It is very unlikely google will support this again in the future.
The app isn't the issue. Google dropped ActiveSync support and it's only available to those who are already using it. If those people get a new device then they won't be able to continue to use ActiveSync. IIRC it's still supported for Google Apps (paid) users but I'd recommend confirming that if you're going to consider it.