For each example in this post, I will be linking to the sea otter pools at the Vancouver aquarium. That location has the coordinates of 49.301,-123.131.
To link to it, you would use ‘geo:49.301,-123.131’.
Depending on your web browser, pasting that into the search bar might prompt you to select which map website you want to use to view that location. For me in Firefox, it asked me to pick between Google Maps and OpenStreetMaps. It’s even more convenient on mobile, where it asks me which map app I want to open it with. Both CoMaps and Google Maps handled it correctly.
If you are writing a post or comment on Lemmy/Piefed/etc., you can place it in the second part of the markdown link format: [Sea Otter Pools](geo:49.301,-123.131). This would output like this: Sea Otter Pools
The linked OpenStreetMap wiki page has a good summary of how well various apps support this scheme. A lot of people here are active in the open source space, so please consider following up with the apps that are currently missing support or have partial support for this.
Cool stuff, but don’t use this for your business. You want actual links that will always work regardless of browser support for Geo. You want your customers to easily retrieve information so you gain their business.