3 Things by Jason Mraz is in G at 200 beats per minute and runs 2:30 across 107 bars. It uses 8 chords — G, C, D, Em, G5, N.C., Em7, D7. 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? 3 Things guitar melody tab.