A Chirp You Can Hear

Keys wedged in a coat pocket or sofa cushion turn up by sound, not by map.

Crowd-Finding Network

A bag left in a taxi only reports back if other phones nearby can relay it.

Precise Close-Range Aim

Once you are in the right room, direction and distance beat a dot on a map.

Fits a Wallet or Keyring

A tracker only helps if it rides along without bulking out a back pocket.

Battery You Can Replace

A dead cell in a sealed tag means buying the whole tracker over again.