A free program for Android, by natnag.
This is a Japanese manga (book) app that includes various illustrations of the human body, including the face, hands, feet, legs, etc. Each part is divided into several illustrations, and there are several things that you can learn from them.
The first is that the face, hands, feet, etc. are not just flat shapes, but have different angles and curves.
Secondly, you can learn how to draw a specific part by observing how it is drawn in the illustrations, and by drawing your own.
The third is that the human body is not a single, uniform, unchanging object, but is instead a collection of different things that change over time.
The fourth is that the same parts have different functions. For example, the hands are used for eating, the feet for walking, and the face for expressing emotions.
The fifth is that human beings are not just one species, but are instead a collection of different species that live together and interact with each other.
Finally, the app teaches you how to draw your own illustrations of the human body, in a simple and easy-to-use way.