Mix yogurt, mayo, sugar, and salt in a bowl. Combine until smooth and creamy for a delightful dressing.
Prepare Pineapple, Apples, Grapes, Celery, and Walnuts. Dice them into bite-sized pieces for a delightful crunch.
Combine Fruits, Nuts, and Dressing. Pour the creamy dressing over the fruits and nuts. Stir well to coat everything in the heavenly mixture.