To setup your Google Apps account on an Apple iOS device including iPhone, iPad or iPod Touch to work with Google Sync, please follow the link below.
This method requires manually setting up your Google Apps account on your iOS device which is a bit more complicated, but will allow you to sync your email, contacts and calendars to your iOS device in "real time" using the built-in Mail app on your iOS device. This will also allow your Google Apps domain administrator to remotely manage and secure your iOS device remotely.
IMPORTANT: In the article below, when Google refers to your "Google Account email address" and "Google Account password", these are just the email address and email password that Trioptek will provide to you for your new Google Apps account.
How to Setup an iOS device with Google Apps for Business: http://support.google.com/mobile/bin/answer.py?hl=en&answer=138740