Which Bluetooth Headphones Switch Easily between 3 Devices?
AirPods!


You can switch devices easily


Airplay in apps that support it
iPhone Control Center: Swipe Up, Swipe Right to Left, select AirPods in Airplay on bottom
iPhone Bluetooth: Force Touch "Settings", select Bluetooth, connect
Mac Bluetooth in Menu Bar (if not there, go to System Preferences → Bluetooth → "Show Bluetooth in Menu Bar"
Mac Sound in Menu Bar (System Preferences → Sound → "Show Volume in Menu Bar")

AirPods auto-pair to devices signed into the same Apple ID (no need to pair via Bluetooth). It connects to the last connected device automatically.
Sound quality/fit are essentially identical to traditional Earpods, but Airpods are truly wireless!