Google's official Enterprise Blog today announced a new iPhone and iPad app to manage your Google Apps domain. Google Admin, available free in the App Store, lets you manage Google Apps users on your domain, change passwords, access support, review and filter logs, access group management features such as adding and viewing group members, deleting individual group members and more.
If you're an administrator hosting your domain on Google Apps, the app should be a no-brainer, but keep in mind you're still going to have to access the web interface to use some of the more advanced features...