I have singing Animatronics high on a shelf, out of my reach. The Animatronic is (de)activated with a button that shorts two wires together. How can I modify the Animatronic with an Arduino so the Animatronic can be activated via an Arduino Manager button on my Apple Watch? When the virtual button is pressed, it should send a signal to the Aimatronic to play/stop its song.
Once you have found the polarity of the voltage on the two pins, you can emulate switch contacts with an optoisolator output. The input is just like a LED circuit (because it contains a LED). The rest is just communications programming (I assume you have done some other projects using this Apple watch?).