Evidence suggests that a diet rich in fruits and vegetables may reduce the risk of chronic diseases such as cardiovascular disease and cancer, and phytochemicals found in fruits and vegetables, such as phenolic, flavonoids, and carotenoids, may play a key role in chronic disease risk reduction. Apples are a popular fruit that are high in phytochemicals, and epidemiological studies have linked apple intake to a lower risk of some malignancies, cardiovascular disease, asthma, and diabetes. Apples have been shown in the laboratory to have high antioxidant activity, prevent cancer cell growth, reduce lipid oxidation, and lower cholesterol. Apples are high in phytochemicals such as quercetin, catechin, phloridzin, and chlorogenic acid, which are all powerful antioxidants. The phytochemical content of apples varies significantly across various kinds, and there are also minor variations in phytochemicals as the fruit matures and ripens. Apple phytochemicals are little to no affect by storage, but they are significantly affected by processing. While there is a lot of data out there, there hasn't been a comprehensive assessment of the health benefits of apples and their phytochemicals. The goal of this article is to examine the most current research on the health benefits of apples and their phytochemicals, as well as phytochemical bioavailability and antioxidant behavior, as well as the impacts of variety, ripening, storage, and processing on apple phytochemicals.