If a city turns red, it’s about to overflow. Send an extra plane immediately.
If you want to play the game safely and support the developers, use these official platforms: Pobierz za darmo Fly Corp (v0.2.407)
"v0.2.407" is an older build; you will miss out on new planes, cities, and bug fixes. If a city turns red, it’s about to overflow
The most stable version with automatic updates and cloud saves. If a city turns red
Don't just buy new routes; upgrade existing airports to handle more passengers.