App

Shortening.

Full definition of app

(plural apps)

(computing) An application (program), especially a small one designed for a mobile device.

1999, February, A visual tool can be thought of as a graphics app that generates most of your program's GUI code for you
1999, Jerry Bradenbaugh, JavaScript application cookbook, So is a spreadsheet app, but I'm not going to put those on a web site any time soon.
1999, November, The Web browser was the killer app that kickstarted the Internet and, in turn, enabled it to be embedded in everything
2005, May, Want realtime flight and gate updates? A calorie counter? A remote for your DVD player? Chances are there's an app for it. Smartphones separate themselves in another key area: connectivity

2007, Evelyn Spence, Explorer's Guide Colorado's Classic Mountain TownsThe food is some of Breck's best: apps like sweet potato gnocchi with smoked chicken and sage cream...
2009, Robin Asbell, New VegetarianIf you lay out a platter of these exciting, beautiful vegetarian appetizers, the other apps will pale in comparison.
2010, Bill Allen, Grillin', Chillin', and Swillin' (page 1)This is not to say that we only serve apps at dinner parties. Quite the contrary; but for smaller gatherings, good appetizers can distinguish you as a host who puts more thought and effort into his or her party menu. Better yet, most apps are relatively easy to make...

(military) application (not a computer program)
(sports) an appearance in a game (e.g., a player with 10 apps in a season played 10 times)