In a Dutch oven heat cooking oil over medium heat. Cook and stir onion, carrots, and celery in hot oil about 10 minutes or until crisp-tender. Reduce heat to medium-low; add apples, curry powder, and salt. Cook, covered, for 5 minutes. Stir in the chicken broth, water, and undrained tomatoes. Bring to boiling; reduce heat. Simmer, covered, for 10 minutes. Stir in the chicken or turkey; simmer for 10 minutes more.