Apple AirTag and Chipolo POP are the two trackers our mounts are built for. Neither one prevents theft — they help you locate a bike afterwards, and only when another phone in the crowdsourced network passes close enough to report the tracker's position.
AirTag works only with Apple's Find My network and needs an iPhone or iPad to set up. In cities with many iPhones, that network is dense and updates often.
Chipolo POP works with either Apple's Find My network or Google's Find Hub network, so it suits Android riders too. Important detail: it uses only one of the two networks at a time — it cannot be found by both simultaneously. Switching means resetting the tracker, removing it from the network it is registered with and pairing it again on the other one.
AirTag supports Ultra Wideband precision finding with recent iPhones, which helps in the last few metres — for example inside a shed or a bike room. Chipolo POP relies on Bluetooth proximity and sound instead.
Both use a user-replaceable CR2032 coin cell that typically lasts about a year. Because a hidden mount is not somewhere you check daily, note the date you installed the tracker and replace the battery on a yearly schedule.
Both can ring. On a bike that is a mixed blessing: it helps you find the bike in a rack, and it can also help a thief find the tracker. Keep the holder out of sight so the sound is muffled and the tracker is hard to spot.