An apple pie is a fruit pie

Pie

A pie is a baked dish which is usually made of a pastry dough casing that covers or completely contains a filling of various sweet or savoury ingredients....

 (or tart) in which the principal filling ingredient is apple

Apple

The apple is the pomaceous fruit of the apple tree, species Malus domestica in the rose family . It is one of the most widely cultivated tree fruits, and the most widely known of the many members of genus Malus that are used by humans. Apple grow on small, deciduous trees that blossom in the spring...

s. It is sometimes served with whipped cream

Whipped cream

Whipped cream is cream that has been beaten by a mixer, whisk, or fork until it is light and fluffy. Whipped cream is often sweetened and sometimes flavored with vanilla, in which case it may be called Chantilly cream or crème Chantilly ....

 or ice cream

Ice cream

Ice cream is a frozen dessert usually made from dairy products, such as milk and cream, and often combined with fruits or other ingredients and flavours. Most varieties contain sugar, although some are made with other sweeteners...

 on top. Pastry is generally used top-and-bottom, making it a double-crust pie, the upper crust of which may be a circular shaped crust or a pastry lattice woven of strips; exceptions are deep-dish apple pie with a top crust only, and open-face Tarte Tatin

Tarte tatin

Tarte Tatin is an upside-down tart in which the fruit are caramelized in butter and sugar before the tart is baked.- History :...

.
Cooking apple

Cooking apple

A cooking apple is an apple that is used primarily for cooking rather than eating fresh. Cooking apples are larger, and can be tarter than eating varieties. Some varieties have a firm flesh that doesn't break down much when cooked...

s (culinary apples), such as the Bramley

Bramley (apple)

Malus domestica 'Bramley's Seedling' is a cultivar of apple which is usually eaten cooked due to its sourness...

 or Granny Smith

Granny Smith

The Granny Ramsey Smith green apple is a tip-bearing apple cultivar, which originated in Australia in 1868. It is named after Maria Ann Smith, who propagated the cultivar from a chance seedling. The tree is thought to be a hybrid of Malus sylvestris, the European Wild Apple, with the domestic...

, are crisp and acidic.