[iOS 26] BLE local name in Advertisement getting truncated – Works on older iOS

Question

Created 16h

Replies 1

Boosts 0

Participants 2

PLATFORM AND VERSION Model - iPhone 13 Pro Max (Potentially for other models also) OS - iOS 26

DESCRIPTION OF PROBLEM : BLE discoverability (advertising) is not working on iOS 26 but works reliably on older iOS versions.

Details: Our app acts as a Bluetooth peripheral. When advertising, the app only adds CBAdvertisementDataLocalNameKey in advertisement data. Format of local name - "NTDI:103202400001"

We have observed that in iOS 26, the local name is getting truncated. This breaks the parsing logic in our IOT device central code, which expects the full local name to be present. We have also observed that some extra data is getting added to the advertisement data by the OS.

As of now, updating the IOT device logic for parsing is not possible.

STEPS TO REPRODUCE

Create an instance of CBPeripheralManager.
Start advertising with a local name with the format "NTDI:103202400001"
Capture the advertisement data using a Bluetooth sniffer tool.
Observe that the local name is getting truncated

Legacy ADV_IND as received by IoT device (truncated name):

HCI Event: LE Meta Event (0x3e) plen 27 LE Advertising Report (0x02) Event type: ADV_IND (0x00) Data length: 15 Flags: 0x1a TX power: 12 dBm 12 09 4e 54 44 49 3a 31 30 ..NTDI:10 RSSI: -47 dBm

Only partial Local Name (“NTDI:10…”) is present in this primary PDU.

Is it possible to avoid the extra data introduced by iOS or avoid local name truncation?

Boost

Answer 1

Engineer OP

Apple

2h

Are you seeing this issue with the iOS 26 release version?

This was an issue in the early iOS 26 betas, but has since been fixed.

If you are seeing this in the release version of iOS 26, please file a bug report right away.

In your bug report we would need some diagnostics logs as well. So, please go to https://developer.apple.com/bug-reporting/profiles-and-logs/ and follow the instructions for Bluetooth for iOS to install a logging profile on your device. Then reproduce the issue, and follow the instructions at the above link to create a sysdiagnose. And attach that to the Feedback report as well.

If you have separate sniffer logs that shows the interaction, also do include those.

Once done, please share the Feedback ID here, and @mention me in your response so we can take a look at this right away.

Argun Tekant /  WWDR Engineering / Core Technologies

0