Wow! Thank you so much for Your review!
Yes, the game has multiplayer, but only for syncing planes movement. But the stamps and fuel are unique for each user, because it would make game harder to balance from a score perspective (solo players would gain much more points). Coherence worked great for us, because of its worlds system (just drag a prefab of ui and create world in dashboard), and really simple aproach for the basic multiplayer stuff, so its pretty convenient for small projects, but its still in alpha, so be carefull)