Press [H] to toggle this help.

Help:

Buttons in top right will select type of shape to create.
Buttons to select individual shapes in the drawing will be along the right side.
Click the button of the selected shape to unselect it.

Select the color by clicking the color swatch in the lower left corner
Save exports the drawing as a PNG.
Fill/Line will toggle between creating filled shapes or outlines
Delete button deletes selected shape or if no shape is selected the shape last created.
Pressing 'Delete' key will also delete selected shape but will do nothing if no shape is selected
Clone creates a copy of the selected shape.
To Front brings the selected shape to the front of the image.
To Back pushes the selected shap to the back of the image.
Export saves shape data in text format.
Import imports shape data text.

Note: zoom buttons are not functional; I might come back to this project some day and finish them.