The BluetoothAdapter class's getBoundedDevices() method returns a set containing a list of all paired or bounded bluetooth devices. In this case, we're checking to see if Bluetooth is turned off, and if it is, we're turning it on and listing all of the associated devices.
Bluetooth devices can advertise using their MacAddress and Name, but the latter is optional, so you'll see devices without names. I'm guessing that these Bluetooth gadgets aren't designed to be connected to by just anybody, and that they're just advertising because they have to.
Scroll to the bottom of the page and select "About Phone," "About Device," or "About Tablet." Scroll to the bottom of the page and tap "Status." The "Bluetooth address" will appear in the list as you scroll down.