I Want by One Direction is in Am at 128 beats per minute and runs 2:38 across 55 bars. It uses 11 chords — N.C., Am, F, C, G, B, E, F#dim, 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? I Want guitar melody tab.