My question is about accessing the custom properties of provider (CMIOExtensionProviderSource). I have successfully transfer some string data from host app to camera extension using custom properties of the device (CMIOExtensionDeviceSource) but I cannot find the way to access the custom property of Extension Provider (CMIOExtensionProviderSource). I use this code to set the custom property of the device:         let selector = FourCharCode("keep")         var address = CMIOObjectPropertyAddress(selector, .global, .main)         //deviceId: CMIOObjectID         let exists = CMIOObjectHasProperty(deviceId, &address)         if exists {             var settable: DarwinBoolean = false             CMIOObjectIsPropertySettable(deviceId,&address,&settable)             if settable == false {                 return             }             var dataSize: UInt32 = 0             CMIOObjectGetPropertyDataSize(deviceId, &address, 0, nil, &dataSize)             var newCommand: CFString = "command string here" as NSString             CMIOObjectSetPropertyData(deviceId, &address, 0, nil, dataSize, &newCommand)         } As I understand to set the property of provider I have to pass CMIOObjectId of Provider. I tried to use kCMIOObjectSystemObject, but unsuccessfully.         //To use Extension Provider instead of Control Camera, Provider CMIOObjectId should be passed to CMIOObjectSetPropertyData instead of deviceId         let exists = CMIOObjectHasProperty("ProviderId", &address)         //this doesn't work, exists == false         let exists = CMIOObjectHasProperty(kCMIOObjectSystemObject, &address) Has someone used CMIOExtensionProviderSource custom properties and can help with that?

I have one query, can we do something like , when our App running at that time only its shows in Third party App like quicktime. When I close my App it Remove from device list of third party App. I have implemented this that way: The host app periodically send information about active devices to extension (just JSON format) Extension checks active devices and adds/removes devices according the list of p. 1 Extension periodically checks the last time the list of active devices was sent and if time interval is more than defined (let's say more that 5 sec), extension removes all devices. The transport was used to send the list of active devices - custom device property. The only problem - you should keep one device as "control device". Probably communication is possible using Extension Provider custom properties but I cannot access them from the host app.