Yes, Producers can join using the iOS app or Android app.
Using the mobile app, they can assist the Host by accepting participants waiting to join the Studio and monitor the recording.
Use your computer or the Riverside mobile app to send a Producer invite to someone. You can also join your own Studio as a Producer using the mobile app.
NOTE:
If you join your own Studio as a Producer in the mobile app, join as the Host from another device to start and stop the recording. Join as a Producer from a computer for additional participant management functions.