To watch movies or anything else, tap the app such as YouTube or Netflix. Selectables are in red.

Note: Make sure you have the "What's On" tab selected (see screenshot)
Chromecast for iPhone -What is Chromecast? Chromecast is a media streaming device that plugs into the HDMI port on your TV. Simply use your mobile device and the TV you already own to cast your favorite TV shows, movies, music, sports, games and more. Chromecast works with iPhone, iPad, Android phone and tablet, Mac and Windows laptop, and Chromebook.