If you’re waiting to stream sports over Chromecast here in the US, well, you’re out of luck (no surprise there, really); if you’re in the UK, however, BT Sport is the first to offer any kind of streaming sports over Chromecast. The app itself is essentially unchanged – BT Broadband customers get access to BT Sport 1, BT Sport 2, and ESPN, all of which are now able to stream to the TV.
Apart from that, it’s the standard “minor bug fixes” bringing BT Sport app for Android up to version 1.3.15. Of course, you’ll need to be a BT customer, which means you’ll need to be living in the UK with your Chromecast