Before and after that, they operated various models of Fokker bi-planes and Tri-Planes including the DR-1 and D-VII.
Well.....ummmm.....No. There were no Fokkers in combat at the Front before 1915.
The Fokker E.I (derived from the Fokker M.5 experimental design) reached the Front in the summer of 1915 as the first armed German fighter.
It was not until early 1915 that the French pilot Roland Garros came up with the idea to fire a machine gune through the propellor by mounting steel delector plates on the blades. It was not until 1 April 1915 that Garros shot down a German Albatros B II reconnaissance aircraft to inaugurate the era of fighter aircraft. On 18 April 1915, Garros was forced to land behind enemy lines near Courtrai. His Morane-Saulnier aircraft was inspected by the Germans and his secret discovered.
Anthony Fokker, however, improved on Garros primitive deflectors by designing an interrupting mechanism that prevented the the gun from firing when the propellor was in the way. The mounting of this new technology on his Fokker E. I begat the first German fighter and the armed Fokker E.I reached the Front in the summer of 1915 inougurating the "Fokker Scourge".
The Fokker Dr. I (the famous triplane) did not go into production until the summer of 1917.
The Fokker D. VII went into production after the design won the competion for new fighter design at Aldershof airfield in January 1918.
Earlier Fokker biplanes from D.I through D. V, produced after the Fokker Eindecker's quickly became obsolete as they were outclassed by the Albatross D.I's and D.III's at the Front and were relegated mostly to rear line training duty. The later D.VI was quickly outclassed by the contemporaneous D.VII.
Before you continue debating me on the details of World War One aviation, it is only fair to warn you that I have had some of my material published in Over The Front: Journal of the League of World War One Aviation Historians :-)