I Know You by Skylar Grey is in Db at 74 beats per minute and runs 4:49 across 66 bars. It uses 19 chords — Fm, Fsus2, Db, Ab, Ebsus4, Eb, Bbm, Cm7, 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 Know You guitar melody tab.