The custard apple is a fruit that has a custard-like consistency when ripe. The custard apple is also called an “anona” and is related to the “sugar apple”. This fruit is often eaten raw or made into jams, jellies, and sauces. Custard apples are often used in desserts, especially tarts. The custard apple is a fruit that has a custard-like consistency when ripe. This fruit is often eaten raw or made into jams, jellies, and sauces. Custard apples are often used in desserts, especially tarts.