Key Features Works with Apple Find My: Simply use the pre‑installed Find My app and add the SmartTrack Card under “Devices”. Never Miss an Alert: The card emits a loud alarm that can be heard even when covered or in another room. Waterproof with Long‑Life Battery: The waterproof coating keeps the card protected, even in the rain. Includes a non‑replaceable battery that lasts up to 3 years. Free Left‑Behind Alerts: Prevent losing items with instant left‑behind notifications via the Find My app — completely free. Find Your Phone in Silent Mode: A quick double‑tap makes your phone ring, even when it’s set to silent. Share with Friends & Family: Use the eufy Security app to share item locations with trusted people. Compatibility: Not compatible with Android devices.