You can use different instruments and pitch for each layer
Tempo changers help you make faster parts of a song without having very high bpm
You can quickly create a song by importing a MIDI file and editing it, not all songs are convertable directly, you might need to edit it a bit.
You can also quickly create a song from audio / video, this is an experimental feature and not very accurate
You can add breakpoints to the timeline (the bar below the composer) to quickly jump between parts of a song
Song Settings
BpmBeats per minute, the speed of the song. Usually the BPM inside the app should be 4 times the BPM of the song you are trying to compose
Base pitchThe main pitch of the song
Base reverb (cave mode)Makes it sound like you are in a cave, this is the default value applied to every instrument
Composer Settings
Beat marksThe number of beats per measure, 3/4 is 3 beats per measure, 4/4 is 4 beats per measure
Note name typeThe type of text which will be written on the note
Number of visible columnsHow many columns are visible at a time, more columns might cause lag
Autosave changesAutosaves the changes to a song every 5 edits, and when you change page/change song
Put next/previous column buttons around keyboardPuts the buttons to select the next/previous column on the left/right of the keyboard
Autoplay in all tabs (pc only)Advanced feature, it syncs other browser tabs to all play at the same time
Lookahead timeHow many milliseconds ahead the composer will look for notes to play, a higher value improves playback accuracy but feels less responsive