You can create a new edge with a long press on an unselected node and without releasing, you can 'pull' an edge out of the node. Then either directly drag the edge tip to another node or release it and create some bends by taps (finally click on a node to finish edge creation).
If the node is selected, the long press will drag the node instead of creating an edge.
Unfortunately, there is currently no documentation on those interactions. However, we try to provide a short documentation in a future update.
