The development blueprint is here: https://couchers.org/solutions/the-build/
I’m not a developer, but maybe it’s helpful to talk about it in general terms… because in my understanding any modern website that offers a range of functionality is basically an app. Take this forum, it’s a Ruby on Rails app running on the server, accessed through a single page web app in the browser. The plan for the Couchers platform seems very similar.
Any “native” mobile app would use the same server backend and just have a different frontend. The advantage of native apps vs web apps in my understanding is better performance and better integration of services like notifications, location and integrated look and feel. Probably the biggest caveat is that once you start with different frontends, you can easily end up with differing access to functionality (like with cs) and this can be confusing to users.
So that’s how I understand it: It’s already an app to begin with. On the Couchers.org platform alpha topic, the developers refer to it as the app.
But the frontend will be a single page web app for the time being (and no native mobile application).