This sounds really great! I think it's clear that ActivityPub needs to expand into location based information at some point. I also don't see why reviews and discussions of places shouldn't be part of the social web.

As far as I understand what @mangrovereviews@mas.to offers is a very flexible protocol for reviews. I'm not sure if it would be best to integrate it with ActivityPub somehow, or if it makes more sense to add it as an additional protocol to platforms for which it's relevant. The easiest solution I could see would be Fediloc only performing two-way federation through ActivityPub, but broadcasting reviews outwards through the Mangrove standard to maximise their reach. That way reviews will become integrated into services supporting Mangrove, while keeping the benefits of ActivityPub within Fediloc.

Comaps will support Mangrove reviews on Android very soon, and it is already supported in their (more experimental) desktop app. It might also be added to OsmAnd if the team merges the pull request. So it seems the hurdle of making it into map apps has largely been overcome by Mangrove, while the social media aspect of it still needs work. In either case supporting Mangrove at this point is probably necessary to avoid XKCD 927.

I feel a bit awkward coming in from the sidelines as I don't have anything to contribute, but with Mangrove gaining traction I at least know there's a growing demand for a user friendly platform for generating place reviews with it. I don't know how much time and resources you have to dedicate to Fediloc, but it looks really interesting at least. I know I'd use it. :) @privatecoffee@cuddly.space