Android: Since Google released an SDK for the Chromecast, we've seen a bunch of new and exciting Chromecast apps. Cast Store has stepped up to help you find new apps that can stream to your Chromecast.
Strictly speaking, Cast Store is not an actual store (which would be against Google Play's terms of service) but more of a directory. You can browse or search for apps and jump directly to their Play Store listing. There's also a section where you can find recently added apps. Right now, there are only around 80 apps and games, but that number keeps climbing every day.
Of course, you can also check out our post with some of the best Chromecast apps, which we periodically update as new apps come out.