There are more than 7,500 known cultivars of apples. Different cultivars are available for temperate and subtropical climates. Apples do not flower in tropical climates because they have a chilling requirement.
Commercially-popular apple cultivars are soft but crisp. Other desired qualities in modern commercial apple breeding are a colourful skin, absence of russeting, ease of shipping, lengthy storage ability, high yields, disease resistance, typical 'Red Delicious' apple shape, long stem (to allow pesticides to penetrate the top of the fruit), and popular flavour.
Old cultivars are often oddly shaped, russeted, and have a variety of textures and colours. Many of them have excellent flavour (often better than most modern cultivars), but may have other problems which make them commercially unviable, such as low yield, liability to disease, or poor tolerance for storage or transport. A few old cultivars are still produced on a large scale, but many have been kept alive by home gardeners and farmers that sell directly to local markets. Many unusual and locally important cultivars with their own unique taste and appearance are out there to discover; apple conservation campaigns have sprung up around the world to preserve such local cultivars from extinction.
Although most cultivars are bred for eating fresh (dessert apples), some are cultivated specifically for cooking (cooking apples) or producing cider. Cider apples are typically too tart and astringent to eat fresh, but they give the beverage a rich flavour that dessert apples cannot.
Modern apples are, as a rule, sweeter than older cultivars. Most North Americans and Europeans favour sweet, subacid apples, but tart apples have a strong minority following. Extremely sweet apples with barely any acid flavour are popular in Asia and especially India.
Tastes in apples vary from one person to another and have changed over time. As an example, the U.S. state of Washington made its reputation for apple growing on Red Delicious. In recent years, many apple connoisseurs have come to regard the Red Delicious as inferior to cultivars such as Fuji and Gala due to its merely mild flavour and insufficiently firm texture.