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%... )
It is a gem. There are all kinds of fun location/organism-specific tools you can put together with the public read-only data, and owlsnearme is a good example of that. I just used it to check my area and learned there are snowy owls nearby, which is new to me!
The iNat API certainly has some quirks and shortcomings, but in terms of usability it's uncommonly good compared to most biodiversity platforms. I maintain the python API client[1], which is used for data visualizations, doing useful things with your own observation data (which is how I got into it), Jupyter notebooks, Discord bots, and some research/education workflows.
