This computer game is based on BrainTeaser by Wim Nijland (1993 year).Choose digits from 1 to 9, split by reaction method into three groups (1-3-7-9, 2-4-6-8, and 5).The goal is to display all digits except 5, without letting the field be cleared.
The release coincided with the platform's 50th anniversary.
Source code — 
bt.zip