An UML activity diagram modeling tool.
Drag the shape from the right and drop it onto the white left site. You can use this types: initial state, final state, decisions, ObjectNode, Action and Note:
To create a connection, click on a button and you will see a cross. Click with the cross on a shape, drag to the other and release the mouse button.
Labeled Activity Edge
To delete an edge click on this button. Click and drag from one to another shape and the edge will be deleted.
If you chose "only one edge", you could connect only one time. Otherwise the edge-button is enabled until you click again on it.
Here you can find informations about activity diagrams