Setting up ACCmail for mobile devices

Set up iPhones and iPads to Display Multiple Calendars

BlackBerry
Google will NO LONGER support - BlackBerry setup for Google Apps November 22, 2011. BlackBerry users can continue to access Gmail through the mobile web app at in their BlackBerry web browser.
iPhone
Set up Google Sync on an iPhone Set up an iPhone with Google Sync to access Google Apps mail, contacts, and calendars using the phone's native applications.
Android
No setup required! Users just launch the pre-installed Gmail for Mobile application from their Android phone.
Android Help Center More about using Gmail for Mobile on an Android device.
Windows Mobile
Set up Google Sync for Windows Mobile Set up a Windows Mobile device with Google Sync to access Google Apps mail, contacts, and calendars from the phone's native applications.

Find these resources and more at the Google Apps deployment site.