I know a lot of people are using iPads now for cooking, but I don't have one, and probably never will, so this is the closest I'll get: a recipe from a book on the Kindle.
Wicked Blueberry Coffee Cake
1/2 cup softened butter
1 cup sugar
3 eggs, slightly beaten
1/2 teaspoon vanilla
1 teaspoon baking powder
1 teaspoon baking soda
1/4 teaspoon salt
2 cups flour
1 cup sour cream or vanilla yogurt
2 cups blueberries (fresh or frozen)
1 cup brown sugar (I used Sugar in the Raw, as always)
1/4 cup butter
1/4 cup flour
I used the KitchenAid mixer until it was time to add the fruit. I gently stirred in the blueberries.
Cream the butter and sugar.
Add eggs, vanilla, baking powder, and soda.
Add flour alternately with sour cream.
Fold in blueberries.
Put into greased 9x13 pan.
In a separate bowl, mix sugar, butter, and flour.
Spread on top of batter.
Bake in preheated 350ºF. oven for 30 minutes.
I didn't have the 1/4 cup butter softened for the topping, so I mixed the sugar and flour, and then cut in the cold butter with two knives.
Seemed to work just fine.
I ate some on the porch in the waning light of evening. Perfect.