Recently tested with the Nut app and confirmed it is working perfectly (sound and connection).
The original battery has been removed for storage to prevent leaking. It requires a CR2032 coin battery (not included, but available at Dollarama for cheap).
Works with both iPhone (iOS) and Android via the "Nut" app. Best used for anti-lost alerts and finding items within Bluetooth range (approx. 30-50ft).