Sony SRS-XB3 Help Manual page 28

The app may not be downloadable in some countries/regions.
Start "NFC Easy Connect" on the smartphone.
3
Make sure that the app screen is displayed.
Touch the speaker with the device.
4
Unlock the screen of the device beforehand.
Keep touching the device on the N marked part of the speaker until the device responds.
If the speaker is off, it will turn on when the device touches it.
Follow the on-screen instructions to establish the connection.
When the BLUETOOTH connection is established,
To disconnect, touch the speaker with the device again.
(BLUETOOTH) indicator stays lit.
23