No, not on the mobile device but there's nothing stopping you putting a waypoint for your friends address or any other place on the chart and then when you sync it will transfer to your device and stay there until you decide to delete it.Just right click over the location and create a waypoint, then right click on the waypoint and take a look under 'view with google maps' to verify you have the right place, if not you can work out where you need to be and adjust the location of the waypoint as necessary.