Google Apps for business supports both IMAP and POP access to your email. In some situations, you may need to contact your Domain Administrator (that's us!) to enable POP or IMAP access. If you are using Google Apps Sync for Outlook or Google Sync for your mobile device then you do not need to setup email thru POP or IMAP. Contact us if you are not sure which type of setup you need or currently have.
Google has a comprehensive list of email clients and mobiles devices that it supports for POP and IMAP email access for Google Apps users.
Supported POP Clients/Mobile Devices with Setup Instructions: http://mail.google.com/support/bin/answer.py?hl=en&ctx=mail&answer=12103
Supported IMAP Client/Mobile Devices with Setup Instructions: http://mail.google.com/support/bin/answer.py?hl=en&ctx=mail&answer=75726