Omniverse foundation applications are best practice example implementations and configurations of Omniverse extensions. They are provided as a generic template on which developers and customers can customize, extend, and personalize according to their workflow.
Foundation applications can be used out-of-the-box, but, to maximize the true value of the Omniverse platform, customization and extension is highly encouraged. Every developer, customer, user will have their own interpretation of Omniverse foundation applications.
Omniverse foundation apps can be explored here.