@kitten_tech @Edent This is a correct me if I'm wrong thing, but... my understanding was that every AP server will publish any content the client sends. In which case, I'd expect to do this on the client, i.e. the phone app. That's the one with the GPS sensor anyway. Then followers using compatible apps can see your checkin properly even if none of the home servers in between understand the data at all.
Of course, a dedicated website is also useful, especially as a demonstrator. It's just, given the above, I'm hanging out for cool, innovative, niche client-side applications to start taking advantage of the network.