Keep chords simpleI – iii – vi – IV in a major key, or i – VI – III – VII in minor, carry most of the mood. 7ths add the soft, jazzy colour.
Pluck + spaceA short-attack pluck with fairly long reverb and a light dotted-8th delay fills the gaps between notes.
Piano left handTap an empty Piano LH square for the bar's root note. Tap again to step up the scale. Shift-click clears it.
Slowed versionDrop Slowed to 80% for the "slowed + reverb" cut. Pitch falls about 4 semitones.