ntrack

ntrack shares your live location with a group of people you choose — over the
Nostr network, with no accounts and no central server. Locations are
end-to-end encrypted (NIP-44 v2), so relays only ever see ciphertext from a
throwaway sender key that is never linked to a personal Nostr identity. Any
Nostr relay works.

A group is simply a shared keypair. Hand its secret key to the people who
should see you — holding it lets them decrypt, the public key is enough to
send. The key is the membership, so rotate it whenever membership changes.

• Share — publish your encrypted location at a set interval.
• Track — follow your groups on a live map; incoming locations are verified,
  deduplicated and decrypted on-device, each with an "open in maps" shortcut.
• Alert — in a dangerous situation, one tap raises a duress alert (starting a
  share if needed): your updates speed up and a loud, pinned notification
  reaches every group member. A check-in timer can auto-escalate to it if you
  don't confirm you're safe in time.