One of the most challenging aspects of designing for mobile interfaces is the sheer amount of possible aspect ratios of mobile devices. Mobile devices include phones and tablets. Phones tend to be much longer than tablet devices, and a UI that fits perfectly on a phone may overlap or look squished when put on a tablet. On top of awkward resolutions, there are also weird quirks that will affect your UI, such as the notch in the iPhone and the folding screens of the various Samsung Galaxy devices.

Mobile devices also have a different set of inputs and interactions. For example, on a mobile device, you can touch the screen at multiple locations simultaneously, but on a PC, you can only click with your mouse in one place at a time. Mobile devices require on-screen keyboards and other peripherals to perform the same actions that you might perform on a console or PC game.

In this chapter, I will discuss the design considerations around the various quirks...