It was only a matter of time before AllCast developer Koushik Dutta gave us an update on Fire TV support. Amazon launched its new $99 mini set-top box last week, and AllCast and screen Mirror support are now in beta for the streaming box.
Dutta took to his Google+ account recently with a download link for the AllCast receiver APK, which at this point is required for functionality with your Fire TV. While Dutta said the official receiver APK has already been submitted to the Amazon App Store, the team is still waiting for approval.
Those interested in testing it out in the mean time are required to sideload the AllCast receiver APK on to the Amazon set-top box. At that point, once you load up AllCast or Mirror on your Android device, Fire TV should appear as a target for your Android apps.
As you can see in the demo video from Dutta below, he is able to mirror is Android device on the big screen with audio, while noting it is fairly low latency but not low enough for Flappy Bird. By comparison, Fire TV performance is comparable to Apple TV and much better than Chromecast, Dutta said. Due to the fact that he hasn't gotten audio running properly on Apple TV, he considers Fire TV implementation the best of the three.