Either 1. keep them in a global place throughout the life of the app - pros: initialized once, always available - cons: harder to load external simulations (from file, web, etc) in the future 2. keep a local Loader in MainMobile that holds the current Simulation - pros: does not get deleted by being temporary - cons: requires secondary Loader objects whenever we want to show names, descriptions, etc from other simulations Currently, I prefer solution 2.