As for best practices in PrimeFaces web applications, there are best practices that you need to follow in mobile applications as well. The real estate is the chief aspect that separates web and mobile applications when designing.
The following are some important notes that you need to remember before you start designing a mobile application:
Maintain a good contrast between different swatch colors that are used for each mobile component.
Keep the Rich UI forms simple and minimal. It is good practice to design a form with the fewest fields to retrieve data. Usually, these forms should be prefilled to reduce errors that may happen when typing on small touchscreens or virtual keyboards.
For example, use visual calendars instead of typing dates manually in the inputs.
Keep simple menus and navigation styles. Desktop sites display big a menu bar at the top of the screen, whereas it eats up space if you use it. In this case, make a drop-down accordion or icon...