Over the past week or so, I was addicted to upgrading planes in this new game I discovered. I was disappointed when I realized the game crashed when you earn more than 2^31 currency. You can still earn 2.14 billion or less each time and upgrade though, so there’s still room for progress.
Jakilutra 
Unfortunately, the game freezes after I earn more than 2.14 B and I am unable to pass the level, because passing it earns me more than this integer.. Please issue an update to rectify this programming issue. Thank you.
PS I love the game!
11/24/2025. I’ve been playing for a few weeks, and I keep having the same issue. I even went as far as to start over on a new account and still got stuck. I’m on Stage 7 and even have my plane’s level at 980 right now because of how long I’ve been stuck. The devs don’t respond to feedback reports.