bookofjoeiNaturalist
The iNaturalist API is an absolute gem. It doesn't require authentication for read-only operations and it has open CORS headers which means it's amazing for demos and tutorials.
My partner and I built this website with it a few years ago: https://www.owlsnearme.com/
(I realize this is a bit on-brand for me but I also use it to track pelicans https://tools.simonwillison.net/species-observation-map#%7B%... )
I know this app!
I once used it to check whether it would identify some birds that are prevalent in my area.
Not related to the app's fubctionality, but it was pretty funny when I replayed my recording of parrot noises to crop it and the next moment, a walnut shell dropped from the tree above.
Animals apparently don't like being recorded!