Don't know about Chromecast, but I have a Android and I just use a HDMI cable, linking my phone to the TV and Stream the Daily burn app from my phone to the TV.
Most smart phones should have a compatible HDMI cable that can hook up to your TV.
DailyBurn doesn't support Chromecast yet. I was recently told by support that they are hoping to have this feature in the next few weeks.
However, until yesterday, I was able to use the Chrome extension to cast the tab with DailyBurn in it to my television. It worked great! Now my browser is no longer able to find my Chromecast when I'm at DailyBurn.com (but I can cast any other site on the web). Is this the same issue that you are having?
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