I'd like to develop an app for Android TV that can control BLuetooth devices.
Is there any Android TV that could do that ?
Alternatively, could a TV box such as the Xiaomi Mi TV do that ? http://www.mi.com/en/mibox/
Settingsfrom the app menu
Wireless and Networksor
Remote & accessories)
Pairbutton on your speaker (or other device) to start the pairing process
According to this answer on Stack Overflow, you should be able to connect up to 7 devices as long as they are above Bluetooth 4.0. The MiBox you linked to does have Bluetooth 4.0/3.0.
All this considered, yes, controlling Bluetooth devices via an Android TV is possible.