Combine pomegranate juice, balsamic vinegar, Dijon, and honey in the bowl of a food processor; pulse until combined. Keep the blade running and slowly pour canola oil in through the food chute until smooth. Add salt and pepper and set dressing aside.

Toss apples, spinach, pomegranate seeds, pecans, and feta cheese together in a large bowl. Drizzle dressing on top and toss until well combined.