For example say I wanted to landmark a feature like the image's left eye. Here is a GIF walking through the labeling process. http://i.imgur.com/63UXkUg.gifv

I would select "+New Shape" and enter in the name of the shape, in my example "left-eye". This will add the shape to model and enable cross hairs as you drag across the screen. As you click, a landmark point will get added at the XY coordinate you click. I can add as many points to a shape and can add any number of shapes to the model.

Once done, you can select the </> menu item and select "Export Points" to produce something like this: { "url": "http://landmark-tool.herokuapp.com/img/nic_cage.jpg", "lefteye": { "0": { "x": 119, "y": 274 }, "1": { "x": 163, "y": 251 }, "2": { "x": 202, "y": 274 }, "3": { "x": 161, "y": 289 } } }