Born in Bougie, Algeria on May 21, 1963, he was raised in Nice, France.
In 1985 he won the first prize in the contemporary music category at the Yehudi Menuhin Competition. He released a CD with Sony Classical in 1996 called Gilles Apap & the Transylvanian Mountain Boys. He has worked as the concertmaster of the Santa Barbara Symphony in California.
On his own label, Apapaziz, he has released Enescu, Debussy and Ravel: violin sonatas and, on Appassionato No Piano On That One in 2001.
Apap has said "To play all the styles of music, its a real pleasure, a relaxation that classical musicians hardly understand. In classical music, one is sequestered by the notes. To have played with Grappelli, Menuhin or the Irish musicians, that's freed me."
He has played with the Irish fiddler Kevin Burke.