Portable EKG part 2: How does it communicate with my phone?

I had another thread about this device recently: https://www.alivecor.com/en/

It sends data to an app on a smartphone. But I can’t figure out how it communicates with the phone. It doesn’t require BlueTooth pairing. NFC is turned off on my phone. How else could this be transmitting data?

Probably byBluetooth LE beacon. Those don’t require paring.