Proximity Pairing is an Apple technology that is used to pair airPods and iOS devices. These messages carry unencrypted information detailing the status, model, and color of the audio device as well as the power and charging status.
Proximity Pairing itself has been thoroughly reverse engineered by Guillaume Celosia and Mathieu Cunche in Discontinued Privacy: Personal Data Leaks in Apple Bluetooth-Low-Energy Continuity Protocols.
| Field Name | Info | Example | Length | Type | Notes |
|---|---|---|---|---|---|
| btcommon.apple.airpods.prefix | Prefix for AirPods messages | 01 | 1 | Bytes | |
| btcommon.apple.airpods.devicemodel | Device model | AirPods Pro (0x0e20) | 2 | UINT16 | |
| btcommon.apple.airpods.status | Device Status | Both AirPods in case (0x55) | 1 | UINT8 | |
| btcommon.apple.airpods.leftbattery | Battery of Left Pod (x10%) | 9 | 1 | UINT8 | Have seen > 100% |
| btcommon.apple.airpods.rightbattery | Battery of Right Pod (x10%) | 9 | 1 | UINT8 | Have seen > 100% |
| btcommon.apple.airpods.casecharging | Whether the case is charging | No (0x0) | 1 | BOOL | |
| btcommon.apple.airpods.rightcharging | Whether right pod is charging | Yes (0x1) | 1 | BOOL | |
| btcommon.apple.airpods.leftcharging | Whether left pod is charging | Yes (0x1) | 1 | BOOL | |
| btcommon.apple.airpods.casebattery | Battery of case (x10%) | 7 | 1 | UINT8 | Have seen > 100% |
| btcommon.apple.airpods.opencount | Counter for opening lid | 57 | 1 | UINT8 | Weird counter |
| btcommon.apple.airpods.devicecolor | Device Color | White (0x00) | 1 | UINT8 | Changes for beats |
| btcommon.apple.airpods.suffix | Suffix for AirPods messages | 00 | 1 | Bytes | |
| btcommon.apple.airpods.encdata | Encrypted Data | 9672711ae6a965737c80d805039773d1 | 16 | Bytes | Not sure what this is |
| btcommon.apple.airpods.batterystatus | AirPods L/R Battery Level Byte | 88 | 1 | None | This is a tree |
| btcommon.apple.airpods.charingstatus | Charging Status Byte | 8f | 1 | None | This is a tree |
| btcommon.apple.airpods.casebatterystatus | Case Battery Level Byte | 8f | 1 | None | This is a tree |
| btcommon.apple.airpods.batterychargingstatus | Battery and Charging Status Bytes | 888f | 2 | None | This is a tree |
The message fields, observed values and their meaning:
- Type: 1 byte, 0x07 -- indicates a Proximity Pairing message
- Length: 1 byte, variable -- number of bytes in the message
- Undefined: 1 byte, 0x01
- Device Model: 2 bytes
- Status: 1 byte -- Indicates the position of the airPods (ear/case)
- Battery Level: 1 byte -- airPod Battery Level Indicator, where the 4 MSBits are the right battery and the 4 LSbits are the left battery.
- Power Charging Status and Battery Case Level: 1 byte -- Battery case and the Left/Right airPod Charging status, and the airPod case battery level
- Lid Open Counter: 1 byte
- Device Color: 1 byte
- Undefined: 1 byte, 0x00
- Encrypted Payload: 16 bytes