3D-T Transponder is an app for anonymous sharing your location and status with other people. It does not require you to enter any personal information and no registration is required. It works just like a radio. Just tune into a channel and see the location and status of other people on this channel. You can sent a message to all users on the channel to let them know of your status. You can use 3D-T Transponder to keep track of other people or vehicles during group events.