I've worked a little on a new app,
TileDist.
https://drive.google.com/file/d/1nslmQMsBqmaO4cZSSF02SGQP2GHPNPaD/view?usp=sharing

It's not complete, but I think it's already useful.
What is it?
It's a simulator for finding nice dual graphs, where the graph infinitely repeats.
Vertices of the dual graph are repelled from each other. The red parallelogram shows how the graph repeats. It's defined by 2-d vectors U and V.
Vertices are repelled from each other if they get too close.
Edges are implicitly defined by Delaunay Triangulation. As the vertices move around, the edges are adjusted. Simply moving a vertex can provide a new graph!
How to use it:
Add a vertex -- position the mouse and press a number key
Change a vertex color -- position the mouse over a vertex and press a number key
Delete a vertex -- position the mouse and press <del>
Play/Pause the simulation -- click the top button
You can export the dual graph to "test.dual", and open that file in original HNT simulator.
Here's an example of a TileDist "graph" being exported to the HNT simulator:
