Unique considerations for interactive application design include:
 
1. How the application interacts with the system
     a. Is it synchronized with the video (bound application such as program trivia) or stand alone (unbound application such as a game)?
     b. How will the user access the application?
 
2. What resources will the application require (for example two-way return channel, persistent storage)?
 
Take a look at OEDN's first free Tru2Way / OCAP application - a simple stop watch app.