In this triangle classifier, you can drag around the three points and it will say which type of triangle it is. If sides are equal, lines will indicate that. It also displays the 3 angles measures. I also have my custom dropdown block there if you want to view all the types of triangles.
That's nice. Kinda like Geometer's Sketchpad.
The only thing I would change is to check for degenerate cases: The three points are collinear; two points are superimposed; all three points are superimposed.