What is the maximum number of stacks that can potentially be used in one software?

In iOS programming, multiple stacks may be used depending on the application's architecture. For example, UINavigationController manages a stack of UIViewController, allowing navigation between screens. Theoretically, an application can have several such stacks — for instance, in different tabs of UITabBarController. The maximum number of stacks is not strictly limited but depends on the architecture and needs of the application. Usually, there are several stacks for different sections of the interface.