The GMail team has announced that the GMail app is back in the Apple AppStore. It was pulled out because Google spotted a bug in the notification system, which has now been fixed, so the app is available again for iPhone, iPod touch and iPad (iOS 4+).
Google says that this is only the beginning for the iOS GMail app, and that the development team will continue to add new features going forward. Note that if you are already using the GMail app from Nov 2, you must log out before re-installing it.
If you have missed the GMail app launch completely, the new GMail app was introduced on Nov 2, and featured a clean interface that is consistent with Google’s overall new design language. The user interface was also optimized for touch devices, which means that everything is sized to be finger-friendly.