Polish-German singer making up one-half of the musical project Eff with Felix Jaehn. He has released several successful solo albums including Karton, Bauch und Kopf, and TAPE.
His career began as a pianist and songwriter penning jingles for television shows. He also accompanied comedian Kurt Krömer for many years as a pianist.
In 2009, he was briefly the frontman for the band Balboa. In 2015, he became a coach on Germany's The Voice Kids.
His real name is Marek Ćwiertnia. His father was born in Dortmund, Germany and his mother, Agnieszka Ćwiertnia, was born in Warsaw, Poland.
In 2013, he was featured on the Sido single "Einer dieser Steine."