Halloween is almost here, which means more scary movies, haunted houses, and candy-related indigestion. It also means a whole slew of scary and fun apps for the Apple iPhone or iPod Touch. Whether you want to play a scary game, doctor a photograph to fool your friends, or pick out a great costume, the following apps are sure to make your Halloween memorable. Read on for all the ghosts, zombies, aliens, and vampire heartthrobs you can handle.

1. IAm Vampire: Most of us have had enough of the “Twilight” series by now. However, if you're a teenage girl or just a die-hard fan, you'll have fun with IAm Vampire as you turn you and your friends into sparkly, Twilight-style vamps. If you've read the books or followed the movies at all, then you'll know that poor Bella Swan has been “dying” for hunky boyfriend Edward Cullen to turn her into a vampire. Alas, if she'd only coughed up $0.99, she could have easily done it herself. The app gives you pale, sparkling skin, unearthly eyes, and finishes the job with a few fangs.

2. 100 Horror Stories: This app has 100 of the scariest stories and novels of all times, but it's more than just a book app. Besides Mary Shelley's Frankenstein, Bram Stoker's Dracula, and several Edgar Allan Poe stories, this app also contains 20 spooky sound effects that includes screams, thunderstorms, and others. Best of all, and the reason this app is #2, 100 Horror Stories has an “auot-scare” setting that will play random sounds when you're least expecting it, giving you or a nearby friend a good solid fright.

3. Look-Up: Look-Up is hopefully the closest any of us will ever come to witnessing an alien invasion. A winning combination of game and augmented reality app, Look-Up will turn the world around you into an edge-of-your-seat, interactive space-alien-fighting experience. Just look through the iPhone’s built-in camera and Look-Up will overlay the image with a variety of UFO’s that you must destroy in order to earn points and progress to the next level. More than just a gimmick, this is a very fun game in its own right.

4. The Halloween Scream Machine: One our very favorite apps for Halloween is The Halloween Scream Machine. This app is a perfect way to create the right ambience for your Halloween party, but you can also use it to play a few Halloween pranks. You can set a delay button on one of the scary sounds, then strategically place your iPad or iPhone where some unsuspecting victim will walk past just as the sound goes off. Best yet, you can record your own scary sounds and add them to the scary music tracks.

5. Halloween Costume Generator: When it comes to figuring out Halloween costume ideas, kids have it easy: Spiderman and Disney princesses never go out of fashion. Adults, on the other hand, must answer questions about whether or not to go with a topical reference, whether to make the costume sexy or conservative, and of course how much to spend and whether the costume will be comfortable enough. Halloween Costume Generator is an iPhone app that will help you navigate these rough waters in a fun and irreverent way. Users can enter search criteria and filter the results by mood, occasion, gender, and more. This app is as fun and hilarious as it is downright useful.