Sling Media has added support for Chromecast through their Slingplayer app for iPhone and iPad. Chromecast allows you to send content to your TV straight from your mobile device, and Slingplayer lets you turn that around and watch TV on your mobile device.
With the two combined you can use the Slingplayer as a remote control for changing the channel, navigating the guide, or accessing the DVR connected to the Slingbox, and you can send videos to the TV via the new 'Cast' icon within the app. Conveniently, the Slingplayer app can run in the background so you can keep doing important things like playing Angry Birds while you watch TV.
The SlingTV unit can also be controlled with the app, like a remote in case you own one.
You can download Slingplayer on the App Store for $14.99.