In a 2 qt. saucepan combine diced apples with water ,sugar, and salt at medium temperature until the apples are done but not mushy, about 10 minutes.
While apples are cooking mix cornstarch with 1/4 cup water until dissolved. When apples are done add lemon juice and berry juice, cook and stir until blended. While stirring on medium heat add dissolved cornstarch slowly. Stir contstantly until thickened. Mix in berries and cinnamon. Remove from heat and cool before placing into cooled prepared pie shell. Refrigerate until thoroughly chilled.
Sour Cream Topping:
Dissolve gelatin in 2 Tbsp. water and set aside. Mix the sour cream, sugar, cream cheese, dash of salt in a pan. Warm on low heat until sugar is dissolved and everything is mixed thoroughly, stir and watch that mixture doesn't burn or dry out.
When all is smooth and blended add vanilla and stir. Gradually add gelatin until mixture has a firm consistency of soft pudding, remove from heat. Cool to luke warm. Smooth topping over blueberries. Chill.
May be garnished with whip cream if you so desire.