I bought this particular chess computer based on an advertisement where it was said and shown that "it allows switching between a computer and a human". I expected that I would be able to practice various openings by making the first few moves in a human to a human mode to get the opening I wanted and then switch to the computer mode to practice the variations. In reality, this option is available only without an app and with the maximum ELO 1200 and quite a long time (2-3 minutes) to generate each move. The app works faster and provides variety of strengths, but it doesn't allow switching the partner from a human to a computer during the game that the board does. Overall, the possibility of testing various moves in openings with the computer that I originally wanted looked reasonable. If you could add the feature to the app to switch an opponent during the game from human to computer (and maybe back), that would be great. I hope it's something feasible, This will make your product the best on the market. Kind regards, Roman