“App” is short for “application” referring to a software application. But there is a difference between an “app” and an “application”. You wouldn’t refer to Microsoft Word or Adobe Photoshop as “Apps”, they are full on “applications” with many features and uses. An “app” is a mini-application and generally designed to fulfill a particular purpose.
An “app” typically refers to a program you can download and use on a smartphone or tablet.
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