Place the chicken thighs in the bottom of a 6-quart slow cooker.
In a medium bowl, whisk together the barbecue sauce, apple butter, apple cider vinegar, garlic powder, onion powder, smoked paprika, salt, and pepper.
Pour the sauce mixture over the chicken, ensuring all pieces are evenly coated.
Distribute the diced apple pieces over the top of the chicken.
Cover and cook on low for 6 hours or high for 3 to 4 hours until the internal temperature reaches 165°F (74°C).
Remove chicken from the slow cooker and shred using two forks or serve whole with the sauce and apple pieces spooned over the top.