This is the first application of the new-home system. It controls the GPIO outputs of the Raspberry PI with the help of the sysfs.
To use the channel builder, you just click on the registered application in the applications view. There you will find 3 combo-boxes which show you the available modes, GPIO pins and actions, which you can perform on a pin.
The shown numbers represent the GPIO pins by their BCM number. For more information on which pin has which number, you can check out https://pinout.xyz/.
Although the underlying framework (new-home-application and new-home-core) is not yet considered "stable" by the meaning of "api will not change" and "works without any crashes", this application, as it is, is considered stable under this term.