What is unclear to me is whether a special phone app is required or not. One of the web pages indicates that it piggybacks onto the infrastructure for airtags/android tags (not clear which). Certainly, if I was building these, that is what I would do as getting a custom app in enough phones would be extremely difficult.
Having said that, the claim is also that these tags report temperature as well — but there is a field (personalized name) that could be used to transport that information. In any case, it is an impressively small tracker!
https://celltracktech.com/pages/blumorpho
https://monarchresearch.org/news-and-events/monarch-research...
https://www.cbc.ca/news/canada/new-brunswick/track-monarch-b...
https://www.opb.org/article/2026/09/21/pacific-northwest-mon...
A little pdf guide: https://westernmonarchcount.org/wp-content/uploads/2024/11/M...
Looks like there is an app you can download too that can do stuff like scanning for tags nearby.