LetsMeet is a map based meeting organizer.Organizer and friends can select and choose the places by tapping on markers on a map. Once a choice is made, the particular marker's color changes and is transmitted to others in the session. Purple indicates liked locations and green indicates confirmed locations. Please see the video for a better idea.
OS 2.1 - 4.0.x
Link to this app: http://thebetafamily.com/navigation/letsmeet