Google Chromecast is a 2 inch HDMI dongle which can turn any TV into a Smart TV. The $35 device allows users to stream videos from a phone or tablet to their TV using Chrome over Wi-Fi. It can also be be plugged into an A/V receiver if your TV doesn't have an extra HDMI port.
You can stream content to your TV from your Android phone or iPhone by using apps like YouTube and Netflix. Chrome installed on Windows or Mac can also be streamed.