I recall seeing a thread about how to display which version of the firmware is installed on your Photon. But I have been unable to find that thread again. I seem to recall that as of v0.4.4, you can use a terminal program (like puTTY) to send a ‘v’ to the Photon and it will display the version number. But I have forgotten what Mode the Photon must be in so that you can use the terminal program to send the ‘v’ command.
Here you go 