sorry yurassik - I obviously misunderstood your post
I think Stef might have installed the Honda version?
As to only using it when in reverse - yes, by default the camera turns on (or more to the point, is displayed) when in reverse.
However, I guess you could get clever with it, using the wiring diagrams in the How To to install a switch which allows you to also turn it on when going forward if you wanted to
