Here you can set a custom scale.

The custom scale is here in the key of C. You can initialize it in major or minor and then adjust it with the “ON” and “OFF” buttons to indicate whether the note is in the scale or not. In the screenshot above, C minor is adjusted.

In order to be able to use this custom scale, “Switch to adjusted” should be set to “ON” in the settings screen
Then you can click “Custom” next to “Major” in the main screen. press to show the adjusted scale in the desired key.