This is a free communication tool SWIM developed. Its off the grid. You create a zone, assign keys to members, and distribute those keys. Zone Members can then relay group messages and GPS coordinates anonymously to each other, and the event leader can see everyone at the same time on a tracking map. Swim is not obligated to cooperate with anyone in the US. The message are distributed using a random number over SMS each time. Its totally free, great for coordinating large groups with ease. https://play.google.com/store/apps/details?id=com.ionicframework.zonemanager to become and event/community leader and make zone keys go to zonemaster.cloudapp.net and make an account. This isn't marketing. Swim pays for all associated services for the cause.