Airplay on Chromecast with Google TV through an app

I have a Chromecast with Google TV, and I want to cast content to it from an iPhone. However, the iPhone app with the media only supports AirPlay. There is also no app available for the chromecast by the media provider.

Is there a good app for streaming using Airplay to my chromecast? (Something like AirConnect) I would like if the app doesn't have ads, and the app being open source is always good for me.
(AirConnect doesn't work with the app using Airplay, I'm just using it as an example.)