See that? That's right. iWork on the iPhone and this screen shot confirms it. Stuart Miles at Pocket-lint spotted this in one of the iPhone 4 screen shots. It says "Open in 'Keynote" while viewing an attachment in Mail. Now this should work like the version on the iPad. You an attachment in the mail, and if you have iWork installed you can open it in the iWork suite. However, this has been replaced by a shot saying "Open in iBooks." Well this means that the iWork Suite should make its way across the iOS 4 devices. We will probably hear about this closer to the public iOS 4 launch on June 21st

Source: Engadget