Preheat oven to 400°, rack just above center. Wash all the berries and drain well. In a large bowl, place berries, tapioca, sugar, lemon juice and almond extract. Give it a gentle stir. Let sit for 15 minutes. This is a great time to roll out the pie crust, if you're making your own.
Once lower pie crust is in pie plate, give berry mixture a quick stir and dump it into pie crust, slightly mounding in the center. Take Tbsp of cubed butter and scatter over the of the berry mixture.
Carefully lay top crust over berries. Fold top layer over bottom layer on outside edge, sealing. You can get as fancy as you like with the outer rim. My tried and true is making a fluted-edge, done by pushing my index finger beyond the pie plate while gently pulling the dough back toward the center. Do this all the way around until it's the way you like it.
Cut 3-5 small slits - (you can be as fancy as you like) - into the top crust. I usually make 5 slits in the center, in the shape of a flower. Then, whisk egg white and 1 tsp water in a small bowl. Using a pastry brush, lightly 'wash' the top of the crust (the protein in the egg helps with browning). Then lightly sprinkle cinnamon sugar, or just sugar, or just cinnamon all over the top of the pie.
Place pie in oven and bake for 45-50 minutes, until it's nicely browned and juices are beginning to push through.
Everyone loves warm pie, but this serves best if allowed to almost completely cool before serving. My dad took his slice straight. My husband likes a bit of vanilla ice cream. You can't go wrong either way. Enjoy!