You can add notes by simply clicking or tapping on a string, and dragging to the right. The length of the note on the screen determines the duration of it.
Click/tap and hold on the desired string. Pull to the right to get the desired duration and release the note. The fret selector will pop up; select the desired fret. The note will be displayed with the correct length and fret.
In order to change the fret number of an existing note, simply click/tap on the note to open the fret selector.
If you would like to edit the length of an existing note, click/tap and hold until you see the two selectors on each side of the note. Drag the selectors to change the length of the note.
Creating chord blocks is similar to creating notes; simply click/tap and start dragging right. Before releasing the note, if you keep dragging across the strings, you will create a chord block. After you release, the chord selector will pop up. Select the root note and the chord type.
To edit the duration and the strings of an existing chord, click/tap and hold the chord. This will open selectors on each side of the chord. Drag these selectors to change the duration of the chord as well as on which strings the chord will be.
To edit the root note and the chord type, simple click/tap the chord. This will open the chord selector on the screen where you can change the root note and the chord type.
In order to delete notes and chords, simply select the chord or note you would like to delete and drag it outside of the staff.