Used Anker Eufy Security SmartTrack Card. Selling because I switched to SwitchBot. I used it with an Android device (using the Anker Eufy security app). I believe it can also be used with an iPhone. Purchased in February 2023. The battery is said to last about 3 years, so I think you can use it for another year and a bit. As you can see in the third photo, the battery seems to have hardly been used on the settings screen. It has been initialized for sale. Compatible with Apple's "Find My" (iOS devices only) / Losing things is a thing of the past / Smart tag / Anti-theft tag / Finding things / Find your smartphone / Prevent forgetting / Make your smartphone ring