Are you sure of 'An iOS app cannot act as a Bluetooth Classic device'?
Let's say I'm 85% certain.
The 1812 service can't be added successfully to the client device, so host device is not able to find this service. I got this error:
peripheralManager didAdd service name: , uuid: 1812, error: Error Domain=CBErrorDomain Code=8 "The specified UUID is not
allowed for this operation." UserInfo={NSLocalizedDescription=The specified UUID is not allowed for this operation.}
Right, it does look like they have specifically blocked this UUID.
Question: have you found any other App Store apps that act as Bluetooth keyboard/mouse?
According to (a link which I'm apparently not allowed to copy and paste, shitty forum software) , we found classic HID service a
1124. I succeed when I try to add service 1124 to peripheralManager. But this host device doesn't connect it as a HID device.
I think here iOS system treat 1124 as a custom service over BLE, not over Bluetooth Classic.
Yes, exactly.