What I can do With Chromecast:-
Convert your small screen like Mobile phones, tablets into larger screen. You can cast all content of your mobile phone, iphone, ipad, tablets, laptop etc on your TV. You need a TV with HDMI port. Play Youtube, Netflix, HOOQ etc on your HD TV, browse Facebook, whatsapp, Listen Saavn, Gaana, play Subway Surfers and much more. You can also connect this device with your speakers.
How Google Chromecast Works:-
Plug Chromecast into your HDTV and power up
Connect your phone or tablet to the same Wi-Fi network as your Chromecast
Tap the Cast button