When she or he will be able to write down on paper at least 90% of the sequence, she or he will add another letter of the Koch sequence. Then the application will run with three letters and so on.
I love using this application on my smartphone because I can exercise at any time and anywhere.
NOTE ON GARBLED AUDIO - Garbled audio has been fixed: starting from Android 4.1, 8-bit audio support has been broken; 16-bit audio still works.
73 de IZ2UUF