The Issue
While validating an iPad app that communicated over BLE to a Windows central (intel chipset), an issue
with newer iPad models (iPad A16, acting as a BLE peripheral) was identified.
It was expected that the central device (windows) should initiate bonding/connection and complete successfully, as with earlier. However this did not happen and the connection attempt just timed out.
Packet analysis
On conducting BLE packet analysis the central initiated connection and bonding, but the BLE stack of iPad A16 did not respond to critical requests such as “Exchange MTU Request” and “Pairing Request.”. Instead, both devices exchanged only Empty PDUs until the connection timed out. GATT services on the iPad remained unreachable, even though advertising packets were visible.
Importantly, the same steps worked correctly on older iPads (e.g., iPad 10th generation). This suggests that the issue originates from a Bluetooth chipset or stack-level change introduced in the iPad A16 platform.
Workarounds
This is potentially not a problem in the new iPad Air M3 which seems to be on the old chipset only. It may bear out to be the same for the iPad Mini and Pro as well.
Conclusion
The BLE bonding and connection issue observed with the iPad A16 and windows with intel Bt chipsets highlights a significant compatibility challenge likely stemming from hardware or firmware changes in the latest generation. While older iPads and alternative dongles continue to work as expected, continued monitoring of firmware updates is recommended, and reporting such issues to Apple may help expedite a resolution. For now, cross-platform testing remains essential to ensure reliable BLE connectivity.
