The conclusion I got was that, we could use deterministic urls (just you like you specify `https://{repo-id}-{commit}-{service}.reploy.io`), which can get linked automatically on every PR.
Every PR could trigger an environment to be created, dropping it after it's unused for a given period of time, on every commit, you could get the environment built automatically when you get an user visiting the specific url. This way, you don't waste too many resources, I wasn't able to find how similar is this to what's implemented on Reploy.
Something I'd love to see, is a way to get mobile apps built for these specific environments, it's kind of simple for Android, but not so simple for iOS, so that if I'm trying a specific environment, I can run tests directly from the mobile apps prepared for it. Is there any plan to do this? or any trick to get a similar workflow?
What I dislike is the price per seat, as I don't see a direct correlation between the number of Github users vs the number of environments, for small companies, it tends to increase the costs a lot, which has prevented me to integrate great tools, I'd prefer something more related to the number of active environments, so that you can choose the number that works for your team.
In any case, looks promising, and of course, wish you success.