Fit piecrust into a 9-inch pieplate according to package directions; fold edges under, and crimp.
Cut 3 apples in half, and slice remaining 3 apples.
Combine flour and sugar; cut in butter with a pastry blender until mixture is crumbly. Sprinkle half of mixture in bottom of piecrust, and top with apple slices. Arrange apple halves, cut sides down, on top. Combine 1/4 cup maple syrup and whipping cream; pour over apple halves. Sprinkle evenly with remaining crumb mixture.
Bake at 425° for 15 minutes. Reduce heat to 375°; bake 35 minutes, shielding with aluminum foil after 15 minutes to prevent excessive browning, if necessary. Let stand 15 minutes. Serve with ice cream and maple syrup.