The two UX design principles that are key to creating excellent mobile user experiences are:

Consistency across device experiences. This means that the design of a mobile app or website should match the design of the desktop version, as well as other platforms and devices. Consistency helps users to recognize and trust the brand, as well as to navigate and use the product more easily.Consistency also reduces the cognitive load and confusion for users who switch between different devices12

Prioritization of content and UI elements on the screen. This means that the design of a mobile app or website should focus on the most important and relevant information and actions for the user, and eliminate or minimize the unnecessary or secondary ones. Prioritization helps users to achieve their goals faster and more efficiently, as well as to avoid distractions and clutter.Prioritization also improves the readability and usability of the product on smaller screens34

https://uxcam.com/blog/mobile-ux/ https://uxplanet.org/mobile-ux-design-key-principles-dee1a632f9e6