Chords for 170812 악동뮤지션(AKMU) - DINOSAUR + Thinking out loud 리허설(Rehearsal) [인천 펜타포트 락 페스티벌] 4K 직캠 by 비몽 (). Spark is the smartest and most interesting app to learn and enjoy playing guitar. Spark is an all-around app for beginners and advanced players to learn any song with chords or master new skills with hundreds of lessons and games in Spark.