The whole ‘app’ thing is experimental at the moment. There are known issues and I’m trying to work on them in parallel with the game. Though you might catch something I don’t know about – feel free to share it!
UPD: From what we see for now it works quite stable on desktops. However there are still issues on mobile because of aggressive memory saving policies, as many devices simply try to erase the game after a few days of not playing. In this case see the ‘Troubleshooting’ section.