MailShadow works really well, syncing my hosted Exchange mailbox with Google Apps. All my email, calendar and contact data in my Exchange mailbox are kept in sync with Google via Outlook AND the Gmail web interface, and even on my iPhone. MailShadow is the only solution which lets me sync real-time between my corporate Exchange mailbox and Gmail (my preferred email) on my iPhone. It's also refreshing to have a product which is bug-free and easy to use. I plan to recommend MailShadow to my law firm clients as MailShadow can provide them with cost-effective backup to their Exchange environment.
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