The CronusMax Plus adapts the QuadStick to the XBox consoles or the PS4.
Consider the Brook Super Converter for the XBox One for a simpler and less expensive alternative.
A CronusMax Plus is no longer required for simple PS4 console connections unless additional inputs devices, like eye-gaze or 3rd party joysticks are used. The CronusMax Plus (or a Brook Super Converter) is usually only required when using QuadStick with the XBox One or XBox 360.
The CronusMax is not required for PS3, PS4, or Nintendo Switch consoles or the PC unless you are combining the Quadstick with other input devices.