Malus domestica “Arkansas Black” apple trees.  These trees produce dark red-purple skinned fruit that have terrific flavor. 
This is an heirloom apple first recognized in the 19th Century. It can be used for fresh eating, is great for baking or juicing, and is an exceptional keeper, keeping 3-5 months in your fridge. These apples have a sweet sharp flavor with notes of cinnamon and sugar.