No, Deako backplates work with existing wires in your home. Deako smart products do require a neutral wire which is common in any home built in the US or Canada within the past 40 years.
Yes, Deako switches will fit in your current switch's junction box.
All switches are made for use in the US and Canada, conforming to a standardized height and width. Deako switches can even fit in tight spots where junction boxes may be only 2" deep.
Deako uses Bluetooth Mesh, a leading technology that enables us to get maximum wireless coverage within the home. We get about 300ft between each unobstructed switch, and each switch repeats the wireless signal. Construction materials such as metal can interfere with wireless signals, however in most residential applications this is not a problem for Deako's implementation.
With Deako, you can control each set of lights that are wired to a Deako Smart product.
To control all the lights in your house, install a Smart Switch or Smart Dimmer in each of your switch locations. Then, create a scene to control all of the lights from one switch. Learn more about scenes here.