Android TV is very flexible ecosystem and Android as a whole has historically been open to whatever you want to add if you can write it. When Google Cast came out people loved the idea of a ChromeCast but wanted to skip new hardware and add it to any Android device they had, so that a old phone didn’t just sit to collect dust in a drawer.
Now with Android TV it’s possible that you actually don’t own an Android phone/tablet, but own an iOS device. Now thankfully Google made sure Cast was cross-platform but that still leaves out Apple’s own Airplay. Airtight solves this problem just for Android TV. As long as both iOS and Android TV are on the same network it will work upon install. As of the writing of this article iOS 9 has some issues but devices most should be on iOS10 now.
Airtight is only 99 cents on the Play Store and completely worth the device so if you wanna add Airplay to your Android TV buy the app and support your talented developers making this possible.