Each “product” delivered by older, more primitive systems like iTunes are simply single movie files.
Each product platform:purple delivers is a full-blown 21st century software program, meaning you will never be stuck at a dead end with what you can do with your products.
Want your viewers to be able to tweet still frames to each other? Want them to be able to take notes on certain sections, draw on the movie, participate in live chat, take quizzes, click and drag objects? Want to create experiences of engaging interactivity that make the primitive, limited interactive options of DVD and Blu Ray disc look positively Stone Age?
Then platform:purple is by far your best option.