For graff, not really. The malt makes the yeast pretty happy so I never found yeast nutrient to be needed.
The key for great cider is giving it time to fully ferment, and then condition before racking to secondary, then more time to let it age and let the flavour blend and taste right.
Keep things clean, give it time, I'm sure your like it.
In Primary: Belgium Chimay clones.
In Secondary: Braggot, pale ale, end of the world white.
Conditioning: Mead, Cider, braggot, Belgium Wheat.
On Tap: Clones, Chimay Blue, Red, Porter, malted cider.
Bottles: Far, far, too many to list.