If you mean the Bluetooth audio receiver, you only need to connect the iPhone to use it. Specifically, first make sure that your iPhone has turned on the switch in Settings-Bluetooth; Then press and hold the pairing button according to the instruction of the receiver; Look up the name of the Bluetooth adapter in the Bluetooth options of iPhone, and then click Connect to use it. The relevant introduction is as follows:

1. First, turn on the Bluetooth switch in iPhone Settings-Bluetooth Options;

2. According to the instructions of your Bluetooth receiver, press and hold the pairing button to enter the pairing mode;

3. Go back to the Bluetooth list of iPhone, wait for the name of your Bluetooth adapter to appear, and click the name to complete the connection;

4. If there are multiple audio devices to output, you can press and hold the audio playback control module in the control center, click the share button with multiple concentric circles in a triangle on the right, and choose to switch to the Bluetooth adapter.