This is based only on my own nubbie research, but from recipes alone I'd say alcohol content.
There are all apple ciders and wines. And both can have other fruits added. And you can have both sparkling and still cider as well as wine. So, as of yet, the only difference I have seen is alcohol content, and perhaps the addition of controlling tannins, acidity ect for wines.
But this forum's favorite, EdWort's Apfelwein is basically the same recipe as several other viders I have seen, with higher sugar content leading to a greater ABV.