In terms of screen size, mobile devices have smaller screens than a PC monitor. When viewing webpages or apps, there are some elements that are translated toIn terms of screen size, mobile devices have smaller screens than a PC monitor. When viewing webpages or apps, there are some elements that are translated to accommodate this screen limit. Commonly, there is a button at the right or left, which will reveal hidden elements when it is tapped.
Take the Facebook app for iOS as an example; if you tap the icon on the left side, it reveals the link menus to navigate the app, while if you tap the icon on the right side, it will reveal your online contacts. Most of today’s apps apply a similar approach.