I've done it before and it works with a few caveats. The filtering is configured under: User Roles, <role name>, General, Restrictions, Browser. Your example user-agent strings don't look correct. EAS user-agents strings are different from device type or browser user-agents. For iPhone, the EAS user-agent will be something like "Apple-iPhone/703.144". If you wanted to allow all iPhones regardless of iOS version allowing "Apple-iPhone*" would work. Apple is pretty straightforward. Android EAS lacks standardization and will be a lot more work. Using TouchDown will make your life much easier for filtering. Microsoft updated the EAS spec in Exchange2010 and it allows devices to stop sending the user-agent in the HTTP header after the initial connection setup. Even though this goes against HTTP RFC recommendations, Microsoft chose to make this change to reduce bandwidth consumption. To accomodate Windows devices that use this new EAS spec, I changed my user-agent filtering from a whitelist to a greylist where I denied some strings and allowed others. The final caveat is that user-agent can be changed on some devices. I believe there are Android apps/hacks that allow the user to change user-agent.
... View more