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By clicking on the image in the notes webapp, Ben brings up a pane that lets him add text labels to his diagram, and drag those around. The controls on the side of this pane allow you Ben to insert labels, move them around, navigate around the diagram, and undo or redo actions. If Ben finishes editing the image and wants to come back to it later, clicking the image in the webapp will bring it back up for editing in a smartphone.
Bringing up the app on your phone will pop a canvas into any notes that Ben has open even if he didn't click the drawing icon first.
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