I have been wondering the same, about other developers. I am working on an application that periodically pulls information from a server about a physical objec

I have been wondering the same, about other developers. I am working on an application that periodically pulls information from a server about a physical object (sorry, I can't be more specific than this, so please don't ask). This information needs to be accessed by several different classes, and displayed in view controllers on different tabs. A view controller will pull the information and make it available to all the other view controllers. A singleton provided an effective solution to this because only one data model of my physical object's state can exist at any given time, with the added benefit that I can access it from any view controller without much effort. I may be wrong, but I thought the purpose of a singleton was for models where there can be one and only one instance of your class? Singletons (like other design patterns) were designed to solve a specific problem. But I concede that they are probably overused.