There isn't an easy way to check the firmware of your device on SmartThings, so this method may require a little patience on your end. Hopefully in the future it will be a little more user friendly.
Checking Firmware via My SmartThings
To check your Inovelli device firmware via my.smartthings.com, please follow the instructions below (NOTE: This will require you to have the proper Edge Driver installed)
Login to your my.smartthings.com account
Click on the three dots at the top right and select, "Advanced Users"
Click on, "Devices"
Locate your Inovelli device and click on it (remember, an Edge Driver needs to be installed)
Scroll down to the, "Attributes" section and search for where it says, "Firmware Version" in the, "Value" column (you may have to search for it in the search box)