After a wild party thrown by her high school ex-boyfriend (Robert de Hoog), College student Anna (Hannah Hoekstra, ARNE DAHL) wakes up with a hangover and a new app on her smartphone: the highly-interactive IRIS personal assistant program. At first, the program is helpful with useful information for her studies and translations of Latin phrases for her philosophy class. The program's idiosyncrasies start with popping up at inopportune times and reinstalling itself when Anna tries to delete it, but IRIS starts behaving in a more malicious manner when it shares compromising video of her roommate Sophie (Isis Cabolet) to all of Anna's contacts. IRIS can also install itself on other phones and computers, sharing video it secretly recorded of Anna in the shower when she tries to have the program removed and humiliating a professor with compromising video taken from his own phone. When IRIS starts threatening Anna and her friends - as well as her brother (Alex Hendrickx) who has an experimental computerized surgical implant to aide his physical therapy after a motorcycle accident - Anna starts to believe that IRIS is not merely a virus but has a mind all of its own.

Although it deals with the horrors of smartphone technology - from the invasive ways that cookies track your shopping behavior to exploiting the privacy concerns that arose over the permissions required by Facebook's messenger program not too long ago - APP feels very much like a nineties techno-thriller when some of the concepts were more abstract to viewers, as well as the various "killer phone" movies from MURDER BY PHONE/BELLS, DIAL: HELP, and more recently ONE MISSED CALL (there's a hint that IRIS might be supernaturally-controlled). It's realization of the technological terror would be outlandish if it all were not so over-familiar from earlier examples as IRIS controls security systems, computer networks, traffic lights, medical systems, and the like to terrorize Anna and harm anyone who tries to help her. Although the film wants to say something profound about technology and human communication, it's really just a silly, outdated-seeming thriller whose real hook is the cinematic exploitation of "Second Screen" technology which syncs the film to the viewer's smartphone to offer "enhanced viewing" from photo galleries to video clips at specific points in the film (the film's introduction includes instructions on how to download the IRIS app which can also be found at iPhone and Android app stores).