While I was working at Pebble, I found myself mocking up my applications and partner applications as a series of screenshot and looking at them on the watch.

I created a desktop tool using node-webkit that allows for Drag-And-Drop of images into the application on the Desktop, it would then convert the image to a reduced/scaled PNG with a Pebble “frame” around the image, and then provides linkage between images by clicking and dragging buttons from one screenshot to another. Then a user could “live” demo on the watch, clicking buttons to navigate the same design tree created on the desktop.