There are two ways to find out what firmware version is installed on your Bike or trainer
Through the Simulator
From the Settings button at the top of the screen, find the "About the APP" option. Once there, look for the Sensors section, and next to the device model you will see the firmware version that is installed.
Through the Toolkit app
Once you locate your Bike on the app, if you click on it you will see the information on the firmware version installed.