Crystal Sky is the fourth studio album by German singer Lena Meyer-Landrut. It was released on digital retailers on 15 May 2015 via We Love Music and Universal Music. The album includes productions by Biffco and Beatgees. The sound is described as electronic sounds with pop influences. The lead single "Traffic Lights" was released in native Germany and across Europe on 1 May 2015. Crystal Sky peaked number 2 on the German albums chart.