"For many years, I adapted game controllers for 'collaborative' play, where the challenged user would perform 1-2 important functions of a game, and a peer/sibling/parent would perform the others. I would add accessible buttons or switch inputs (of your own or my switch(es)) and the collaborator would use that controller. I did this for all the game consoles, ending with the Xbox 360 and PS3 generations. I finally got on board the Xbox One (and Playstation 4 (PS4)) 'train' with these new products! And this time, I was aiming for independent play, piggy-backing off the nice Microsoft Xbox Adaptive Controller (XAC)!" RJ :-)
The Microsoft XAC is a box that connects to your Xbox One (or PS4), which connects to one of the USB port on your console (yes, even if you have a PS4! I supply the adapter). My controllers then plug into your XAC's USB port. For button-pressing, you will use the multi-colored accompanying cable to go from my switch *outputs* to the XAC's switch inputs. In this manner, you can choose what my 4 buttons do within your game(s).
The XAC has switch inputs for all the buttons on a regular controller, so you can have my buttons do what you want, or, get just the Directional Button-Pad below and plug your switch(es) directly into the XAC :-) ALSO, the XAC has a Co-pilot mode where you can have a regular controller 'help' the XAC user.
The Small Joystick below, as well as the buttons, are actually "switches", on or off. This joystick is not proportional. But in my long experience, I have found that the small movement of the stick doesn't really lend itself to fine movement, and 'my' users are not great at fine motor control. So, each controller below has a setting for your game 'range', that is, how far your game thinks you are pushing a thumbstick (which it's pretending to be). And you can plug in 2 of my controllers to achieve left and right thumbstick control (usually, your left thumbstick is for movement and the right is for looking around).
Note!! I do NOT supply the XAC. You can get that at BestBuy.com, The Microsoft store, or Target.com ($99).
And for you PS4 people, the adapter I offer (pink one below) plugs right into your PS4 USB port and away you go!
P.S. I still offer my Quad Button Box, now, for Xbox One and, with my adapter, PS4 (using an Xbox controller). Contact me for ordering info at <infoRJ@rjcooper.com>.