At the bottom of the player, the large start button names the selected practice mode, for example "Start In tempo". Its attached arrow opens the choice between "In tempo" and "Note by note". "Play through only" sits separately alongside it.
The start button shows the mode — the arrow next to it opens the choice.
Play through only
Klavissimo plays the exercise or piece once from start to end while the cursor moves along — you just listen, without touching the keys yourself. No pressure, no scoring.
You just listen — the cursor moves along.
In tempo
"In tempo" has you play along at a fixed tempo — a count-in leads you in, then the recording runs. Klavissimo scores whether you hit the right note at the right time.
The accented click is the one — then the recording runs.
Note by note
"Note by note" waits at every note for your key press before moving on — your tempo counts, not the clock. The most relaxed of the three modes, good for getting into a new spot.
Klavissimo waits until YOU play the key.
Good to know:
"Note by note" usually suits a new spot best; once it sits, "In tempo" is worth it. Choose the mode before starting via the arrow on the start button.
Good to know:
With "No piano yet", the on-screen keyboard counts as scored input for "In tempo" and "Note by note". Choose "Real piano" in your profile instead and you get the two unscored acoustic routes "Keep the tempo" and "Follow your playing".