Ever wondered what kind of work goes into creating those GunCon devices? The one you'll use for Time Crisis 4 is different from its predecessors, as it dictates all on-screen movement as well as aiming/shooting. This is something the franchise has wanted to do for a while, but with the GunCon 2 and older consoles, it just didn't seem feasible. As you can see from the picture, early renderings put an analog stick where the gun's hammer would be. It doesn't look that comfortable for moving around a level, honestly, but that's why it's an early rendering and not the final product.
After a month, a prototype was created where two people could move around in a room and try to shoot one another. It only had algorithms for horizontal aiming, which obviously had vertical aiming to add later, but for the gun itself, testing it this way was necessary. We're left wondering about the final stages of the process, as it has yet to be written. It seems a lot of work was put into the GunCon 3, so much so that the game itself seems like an add-on, though it's the reason for the redesign.