status bar: it is mainly used to display the mobile phone status such as signal, operator and power;
navigation bar: mainly displays the name of the current interface, including corresponding functions or jump buttons between pages;
main menu bar: similar to the main menu of a page, it provides a quick jump of the classified content of the whole application;
content area: display the corresponding content provided by the application;
It should be noted that since Android removed the physical keys and used the virtual keys at the bottom of the screen after 4., Android moved the main menu in iOS from the bottom to the top, thus avoiding misoperation of the virtual keys.
Having said that, I have to say that although android and iOS are both mobile operating systems, they still have great differences in UI design. Why is this? In fact, this is basically caused by the closed source of iOS. Because of its commercialization, many designs have been patented. Android must be different in many places. The most talked about is the elastic scrolling of iOS. In fact, to achieve this effect, the ScrollView of Android only needs to modify the value of one parameter. However, due to the patent applied by iOS, Android cannot be used.