Works fine on my iPhone 8 but I get nothing when I plug it into my new iPhone 11, not even the warning of it being unsupported.

Hello and good day ryandetzel. I am sorry for the trouble that this has caused. Have you tried using a different mobile device to see if the issue will still persist? Upon checking the iPhone 11 from the recommended mobile device list. I am sorry to say that the said mobile device is not yet recommended for the DJI Spark and for the DJI Go 4 application. There is a possibility that the iPhone 11 will work on the DJI Spark. However, since it's not yet optimized with our DJI Go 4 application we cannot guaranteed the stability of the the iPhone 11  if it will work all the time while using it on the DJI Spark. Thank you.