re: Chromecast question

If you're using an Apple product (iPhone, iPad, etc.), it will cast the specific application you choose to cast from. For example, open Netflix, start casting to the TV. The TV will just say "Netflix" or something until you actually pick a movie, then the movie will start playing on your TV. Once the movie's playing, you can exit out of Netflix and do what you want on your iPad. Anything other than Netflix won't be cast to the TV until you choose to cast from a different application. (ex: YouTube)

If you want to cast whatever's on your screen, you'll have to cast using a tab in the Chrome browser. Not sure what "non-approved" videos will cast. A friend tried streaming an Amazon movie through a Chrome tab and casting the tab to his TV a few months back, but was never able to get the movie to play on his TV. Haven't checked if that works now or not.

No clue about using a Chromecast with Android products.