AirStreamer enables playing MKV, AVI, and WMV videos on a Chromecast device. All you need to do is turn on your TV and Google Chromecast device and make sure your Mac and Google Chromecast are connected to the same IPv4 Wi-Fi network. Then, you can open your video files by clicking on the menu File -> Open from AirStreamer and wait a few seconds for the video to play back. AirStreamer does not support DRM-protected files.
