App is the first film to utilize “second screen technology,” which basically means a mobile device is recommended to get the full experience. Being a Luddite at heart (who only got a smartphone two months ago) I was really apprehensive about this one. It seemed impossible to thoroughly enjoy a film when you’re also supposed to be sporadically looking down at your phone. “Second screen technology” also sounded like a lame gimmick to compensate for a weak narrative.

I’m happy to report that App is a kick ass thriller on its own and becomes more engrossing at times when the “second screen” tech is used. Of course there are some drawbacks and pointless moments of the experience. And I really hope the tech doesn’t catch on for major releases because it would be frustrating beyond belief to be in a theater of people constantly checking their cellphones. But for some home watching, this “second screen” stuff is pretty damn fun.

App stars Hannah Hoekstra as Anna, a young college student who one night shirks her studies to go to a new tenant’s welcoming party in her building. There she runs into her ex-boyfriend Tim (Robert de Hoog) and proceeds to get shitfaced on memory lane and copious amounts of tequila. But the hangover that greets her the following morning is the least of her problems.

Someone at the party downloaded a mysterious app on her phone: IRIS. At first it performs simple tasks, like searches and intuitively setting alarms for Anna. It’s like Siri, but with an eerie face that pops up onscreen during use. But soon IRIS starts tormenting Anna and those close to her in progressively more damaging ways. IRIS becomes a straight up app anarchist – one that won’t bow down when sim cards are changed out. As Anna struggles to stop IRIS’ reign of smartphone terrorism, she finds herself at the heart of a deadly conspiracy.

The plot is pretty straightforward and most viewers will see the twists coming a mile away. Still, App is a really solid thriller anchored by Hannah Hoekstra’s engaging performance as the hard-nosed, but vulnerable, Anna. The entire cast is really strong, including Isis Cabolet as Anna’s best friend and Alex Hendrickx as her brother. App is a sharp looking film too, with keen directing from Bobby Boermans. The man knows how to construct a thriller without having to over stylize – a crime lots of techno-thrillers are guilty of nowadays.

Does the “second screen technology” actually make the film more entertaining? In some regards it definitely adds weight to the suspense. There are a few moments when off-screen characters text each other and that works really well. Their text conversation comes up on your phone, which raises the tension as you see them scheme in real time. The text messages were definitely the best part of the “second” experience, but the video messages and real time recording of certain events work pretty well too.

Other times the tech is completely superfluous. Alternate angles are the best example of the experience at its worst. These extra shots add nothing to the narrative and felt like they served only to fluff out periods when the tech couldn’t be used for something more interesting. Wisely, Boermans matches up the “second screen” parts to shots in the film that aren’t crucial, so you won’t feel cheated when you look away. An alternate angle on your phone might appear during a long shot of Anna riding her motorcycle, for instance. The “second screen” doesn’t add anything to the narrative, but you won’t miss anything if you peek at it.

For better or worse, App is a big leap forward in the continuing merging of film and technology. Thankfully the filmmakers didn’t sacrifice a good film for the sake of a cheap gimmick. The “second screen technology” isn’t necessary to enjoy the film, but if you’re just kicking it a home, you might as well utilize it. I was genuinely surprised with how much fun I had with it.

App drops on May 9 on all digital platforms (and in select theaters, I think). To download the IRIS app for your iPhone or Android, text “IRIS” to 97000. It reacts to the film’s soundtrack, so make sure you’re not wearing headphones. The IRIS app also includes exclusive character bios and film stills.