September 2019 update: With the release of version 2.0, Signal Spy is now compatible with Android Q/10! One known "issue" is with the Location Permission setting and an "Unknown SSID" error. Read more about it and how to fix it here.
We have been alerted to issues with Signal Spy and dialer codes in general on Android Q.
We are going to be looking into it and will update this thread with information as soon as we have it.
Signal Spy Dev Team