What Is a Mobile Application?

Woman using self tracking app.
Guido Mieth / Getty Images

Mobile applications (also known as mobile apps) are software programs developed for mobile devices such as smartphones and tablets. They turn mobile devices into miniature powerhouses of function and fun. Some devices come preloaded with some mobile apps courtesy of their manufacturers or the mobile service providers with which they're associated (for example, Verizon, AT&T, T-Mobile, etc.), but many more apps are available through device-specific app stores.

Mobile App Functions

The purposes of these apps run the gamut, from utility, productivity, and navigation to entertainment, sports, fitness, and just about any others imaginable. Social media is one of the most popular fields of mobile app development and adoption. In fact, Facebook was the most widely used app in 2017 across all platforms.

Many online entities have both mobile websites and mobile apps. In general, the difference lies in purpose: An app is usually smaller in scope than a mobile website, offers more interactivity, and presents more specific information in a format that's easy and intuitive to use on a mobile device.

Operating System Compatibility

A mobile app developer creates an app specifically for the operating system in which it will run. For example, mobile apps for the iPad are supported by Apple's iOS, but not Google's Android. An Apple app can't run on an Android phone, and vice versa.

Often, developers create a version for each; for example, a mobile app in the Apple Store might have a counterpart in Google Play.

Why Mobile Apps Are Different From "Regular" Apps

Many mobile apps have corresponding programs meant to run on desktop computers. Mobile apps have to work with different constraints than their desktop equivalents, however.

Mobile devices have a wide range of screen sizes, memory capacities, processor capabilities, graphical interfaces, buttons, and touch functions, and developers must accommodate them all.

For example, mobile app users (like website visitors) don't want to scroll sideways to see text, images, or interactive touchpoints, nor do they want to struggle reading tiny text. An additional consideration for mobile app developers is the touch interface common to mobile devices.

"Mobile First" Development

Before the widespread adoption of mobile devices, software was first developed to run on desktops and laptops, with a mobile version coming after. Tablet and smartphone usage is outstripping that of desktop computers and laptops, reflected in app sales trends. In fact, 197 billion apps were forecast to be downloaded in 2017. As a result, many developers have turned to a "mobile-first" approach, mirroring a similar trend in web design. For these apps, their mobile versions are the defaults, with the desktop versions being adapted for their larger screens and more expansive specifications.

Finding and Installing Mobile Apps

As of 2017, the three major players in the mobile apps space are:

Many websites also offer corresponding apps and provide download links.

Installation is fast and easy: Simply navigate to the appropriate store, find the app you want, and download it. Your device will install it automatically once the download completes.