Cook pie crust according to directions. set aside to cool.
Combine sugar, water, cornstarch, and fruit. Cook on medium heat until mixture starts to bubble, then reduce to a medium-low simmer and stir frequently until thickened, about 5-10 minutes. Remove from heat.
Spread cream cheese on the bottom of the cooked pie crust. Pour blueberry and peach filling over cream cheese. Cool for a few hours in the refrigerator.