[TD-Linux]

The footnote says that it requires an iCloud account.

Are these even Bluetooth? Maybe they always remain connected to your iPhone, and the other devices stream to the iPhone first.

[rince]

Looks like these are indeed Bluetooth http://www.apple.com/shop/product/MMEF2AM/A/airpods

Connections AirPods: Bluetooth

And then further down Compatibility: iPhone 5 and up

iPhone 5 has Bluetooth 4.0 So I'm guessing the pairing information is shared via iCloud