Heat oven to 425°F. Unfold pie crust; press out fold lines. With rolling pin, roll crust to form 12-inch round. With 5-inch plate or bowl as a guide, cut 4 rounds from crust, reserving scraps for another use. Place rounds on ungreased cookie sheet.
Divide apple slices evenly onto pie crust rounds. Sprinkle 2 teaspoons toffee bits over apple slices in each tartlet. Fold 1/2 inch of crust over filling, pinching as needed to fit.
Bake at 425°F. for 18 to 20 minutes or until crust is golden brown and apple slices are tender. Serve tartlets topped with ice cream.