In a large saucepan, mix pizza sauce, apple jelly, Italian seasoning, salt and pepper. Bring to a low boil over medium heat.
Place frozen meatballs into the sauce mixture. Cover and simmer over medium heat for 20 minutes, or until meatballs are done, stirring occasionally.
While the meatballs are cooking, preheat oven to 375 degrees F (190 degrees C). Place the split hoagie rolls on a large baking sheet.
Place several meatballs and desired amount of sauce in each roll. Layer with mozzarella cheese. Place in the preheated oven for 2 to 3 minutes, or until cheese is melted.