This app allows you to draw symmetrical patterns. Just place your finger or mouse on the drawing board and draw away. You can select different colours and symmetry types. Symmetries play a really important role in mathematics. Try to observe and describe the regularities in the patterns that you draw.
The visualisation above is an extremely simplified version of the symmetry drawing app iOrnament.
The following video shows how to craft a three-dimensional figure from a pattern created in iOrnament.