Is there any good way to reliably look this up using the Bluetooth SIG Launch Studio ICS details published for every device? For the iPad Air example, Declaration ID: D034810 describes that device, and the referenced QDID: 115456 for the Controller subsystem and Low Energy Link Layer has the extended scanning feature selected/checked. However, per the OP, that device does not support extended advertising when programmatically asking iOS about it. I assume this means the Host subsystem (iOS) doesn't support it, but the Controller subsystem (radio hardware) does (?).... When trying to find an equivalent feature in the Host subsystem, I am not finding what I would expect given anecdotal evidence from anthony@[site].com in the previous comment.