As with what @JDRoberts was saying, to dim an in wall dimmer you a few options. The Fibaro Dimmer 2 allows you to have a default dim level when turned on at the switch and then if you double toggle quickly it will turn it up to 100%. On mine, I have the default dim set to 30% and when I need the extra light I do a quick double toggle. You can fine tune it to different dim levels using the SmartThings app of course. The other option is to use a Momentary wall switch which allows you to hold the button down to dim up and then let go and hold the button again to dim down.
Another option are the Qubino in-wall devices. A little cheaper that the Fibaro and a great device.