I have Google Maps, BBMaps, and Garmin Mobile on my 8830. When I select a contact and press the Menu button, "Show on Google Maps" is an option at the top of the menu. "View Home Map" is an option about half-way down. If I select Google Maps, it shows the location on Google Maps. If I select "View Home Map," it launches BBMaps and shows the location on BBMaps. I used to have Nav4All on my BlackBerry. I'm pretty sure it had added itself as a menu item as well. I can't find any way to get contacts to launch Garmin Mobile, and I can't find any option in Garmin Mobile to enable it. Of course, you can open the contact in "Where To" and select it that way, but that's what you're asking.