Setting up a personal Gmail on your iDevice is a straight forward process. But adding a Google Apps email account can be a bit more tricky. Here’s how to add your Google Apps email address to your iDevice running iOS 5.
Log into your Google Apps account and go to email settings.
Select Forwarding and POP/IMAP and select Enable IMAP.
Now, on your iPhone, iPad or iPod touch go to Settings >> Mail, Contacts, Calendars. Then tap Add Account.
Next, tap Gmail from the list of services.
Make sure to type in your full site email address in the Name and Address field. For example I would type firstname.lastname@example.org in both fields. Enter your password and description and tap Next.
If you have any problems, under Advanced, make sure Incoming Server is set to Use SSL is set to On and the Server Port is 993. Also, make sure the Outgoing Mail Server is set to Use SSL and Server Port 587.
You can now send and receive email from your iDevice via your Google Accounts email address.