First let me describe the requirement. I want to control an electronic equipment with spark core (from an app) as well as with a physical switch. The solution I came up with is to connect the relay along with a 3 way switch as shown below.
The issue is if I turn it off from the switch then there is no way of displaying its state in the app (which is currently off)??
Is there any solution to this ??
Have I got it all wrong (combining with a 3 way switch)?? if so any other solution to control a device by spark as well as with a physical switch??