What is the difference between the ODM App and the Custom App?

ODM: The customer raises the demand, and develops it by themselves. And Tuya integrates the module developed by the customers into the Tuya App, and packages them together into an App which is customized. App: The customer raises the demand, which is developed by the Tuya KAE team, and the module developed by the KAE team is integrated into the Tuya App, and finally package them together into an App.