8 high-tech Halloween pranks to spook your friends

As the month of October comes to an end, a devilish spirit may come over your friends and family: a desire to scare, to startle and to scream.

Most people rely on fairly basic scare tactics, including masks, hiding, and jump scares. They don't realize the potential frightful delights offered by their everyday computers and smartphones. To that end, here are eight unique ways that you can terrorize your nearest and dearest with tech this Halloween season.

One fairly easy way to scare a friend is to use your phone as a random scary sound generator. While there are plenty of apps out there that can help you do it, each requires you to hold the phone while using it. However, there is a way to do set random screams and cries on a revolving timer.

If you download a few creepy alert tones from iTunes or Google Play, you can set them to go off with the Alarm function. Just set 10 to 12 alarms so that alerts go off every 17-32 minutes, hide the phone, then let the chaos commence. You could also try setting the phone off by changing your ringtone to something really terrifying, then call it with a tertiary phone number to surprise your friends.

We've all seen the videos: someone is watching a fairly monotonous video then, suddenly, a scary face and/or loud noise pops onto the screen and scares the bejeebus out of them.

Well, there are folks who made that trick into an app. iPhone and Android users can download one of the many "Scare Prank" apps that looks like a standard game, but will scare your friends after an extended period of time. There are even versions of the app that will scare a friend while they take your picture (just make sure they don't drop your phone)!

Instructables user Mikeasaurus invented a wayto put your head in a jar without actually putting your head in a jar. This prank essentially places an image of your face in a jug of fake formaldehyde that almost looks like the real deal. It requires some photoshopping skill and food coloring, but it's a great way to mess with your coworkers. It'd also be a great prop for a Headless Horseman-type costume.

Image credit: Mikeasaurus

You know what's better than setting up a two-way mirror? Scaring your friends with it. If you get a properly sized photo frame and apply a two-way mirror film to the glass, you can turn your television or tablet into a normal looking mirror. You can then create your own footage or buy some stock footage and set it up so that it plays on loop or via remote command. When your victim looks into the mirror, the footage you picked will play, hopefully startling them in a ghoulishly delightful way.

Image credit: Zack Scott

Most everyone seems to be a little spooked by drones, but why not give everyone a reason to be scared this Halloween? DIY creator Alton Porter released a video last year showing how one could turn a standard commercial quadcopter drone into a ghostly apparition. All you have to do is find a small ghost hanging ornament (adding glowing eyes gets 50 additional cool points), attach it to the bottom of the drone, then fly it around and scare your neighbors. Just make sure you can keep your eye on it.

Do you have a mug that could startle your everyday onlooker? If so, you should consider 3D-printing a mask version of your face. 3D-printing site thatsmyface.com will print a photo of your face (or maybe someone else you think is scary) for you to wear. While you might be as attractive as Anne Hathaway, there's no doubt that surprising your friends or your favorite monster with a 3D mask of yourself will freak them out. A mask costs $299 plus shipping from the site, but the look on your pals' faces may be priceless.

Image credit: That's My Face

Want to be more open with your friends? You should show them your heart with the iWound app. Originally developed by a NASA engineer, iWound is designed so users can wear a smartphone with the app installed under their clothing and trick passersby into thinking that they're actually looking at a bloody wound. While it might not be the scariest thing by itself, it's an easy way of making it look like you have a hole in your chest.

Image credit: Mark Rober

If you have an excessive budget for your haunted house, then you might consider startling your friends with this unconventional door scare designed by special effects company Hi-Rez Effects.

The idea is that you would set up a video display on a fake steel door, which would occasionally show an evil nurse walking towards the door. The nurse will walk around for a while, but eventually she'll take interest in the door and the viewer. As she walks up, she grimaces and attempts to stab a nearby door user with a big metal syringe.

The screen syncs up with a mechanical prop that would attempt to "stab" the viewer with a big syringe – don't be too worried though as the needle is made of vinyl tubing. On the crap-your-pants scale, this could get some big results out of your friends. However, the DVD, video display and mechanical prop cost more than $850 (about £556, AU$1,197) in total. Now that's a frightening figure.

Image credit: Hi-Rez Designs

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