Superstar by Usher is in A at 72 beats per minute and runs 3:00 across 44 bars. It uses 9 chords — Dmaj7, Bm7, C#m7, A6/9, Dmaj13, F#7, D#7, Fdim, and a few more. The chord diagram changes as the song plays and the words light up as they are sung, so you can strum and sing along without reading ahead.
Want the melody line note by note? Superstar guitar melody tab.