Remember flip books? Get a stack of paper and draw something on the first page. On the next page, draw just about the same thing moved slightly, repeat until you run out of paper. Staple the pile together, flip through the pages and if you did it right, your drawings move like an animated cartoon. That, in a few words, is the basis of movement in all animation and motion pictures. When you go to the movies, the projector displays 24 frames per second giving the illusion of movement.

Flip books used to come in Cracker Jack boxes, be sold in stores, and steal hundreds of hours of kids lives who were taken with the idea and who made lots and lots of them. I was one of those kids.

Well, there's an app for that. Cartoon Creator [iTunes link] is a fun app that makes flip books on your iPhone or iPod touch running OS 3.0 or later. Choose a pen and a color and go to work. Draw something on page, click the empty face button and an overlay drops over your first page allowing you to see what you did but also letting you draw a slightly moved version. Wash, rinse and repeat until you have a full animation that will play back at any speed you determine.

The app has some very nice options, like three different pens, each with a thinner or thicker line, lots of colors to choose from, and a bunch of cartoonish sounds that you can attribute to any page. If you are creating an animation of a brick being thrown through a window, why not assign a glass breaking sound to the page where the brick hits the glass?

In addition, and this is something near and dear to my heart, it does anaglyph 3D, (red and cyan) with the appropriate glasses. This works remarkably well. The app gives you the ability to draw on three planes. Along with regular drawing that appears on the plane of the screen, you can draw behind the screen and in front of the screen as well. After digging out my anaglyph glasses, I found this to be some of the best anaglyph 3D I remember seeing. The image is sharp, clear and very dimensional.

This is a really nice app, and a great introduction to animation and 3D. It would be perfect for kids. My flip book period took most of my ninth year. It would also be great if you can actually draw. I have absolutely no talent in this area.

When you run the app, you are presented with a an uninviting lined screen titled 'Cartoons.' Big detriment there, but the web site provides full instructions on how to use the app. This is a problem I've seen with many apps. Load it and then what? At the very least having a link to the site would be a help.

Another problem with the app is that you can't delete anything but a particular page. If you are a screw-up like me and want to delete an entire animation, you can't. Any time you start an animation, an entry named Untitled appears and you can't get rid of it. That may not seem like much of an oversight to someone who can draw, but it's me reviewing this app and a delete option would get more use than anything else.

These two slights are minor and I'm sure can, and hopefully will, be fixed in a an update. As it stands now, it's a fun app, does great 3D, can waste countless hours and might even teach kids about animation.

At $.99US it's worth the money and at the same time you'll get to feel good about yourself when you think of all the trees you're saving.

3D photo apps are not new to the iPhone platform, but a new app from Juicy Bits looks promising in terms of making those pictures with depth a lot easier to take and view.

3D Camera 1.1 [US$1.99, click opens iTunes] is now available for iPhone OS 2.2 and 3.0 devices, and it lets you take photos that use one of three methods to create the illusion of 3D: red/cyan anaglyphs that require those funky 3D glasses, stereograms that create 3D images when your eyes look at them a certain way, and wiggle stereograms (or wiggle-grams) that use animated GIF images to provide the "depth". If you need a place to buy the goofy glasses, Juicy Bits lists several sources on their website

To take the photos, you use one of two methods. If you're planning on taking an anaglyph or sterogram, you take one picture, move the iPhone camera slightly to the right, and take another photo. To make a wiggle stereogram, you point directly at the same object from two slightly different vantage points. The app provides instructions on exactly how to take the two photos each time you launch it.

How are the results? Well, I haven't tried a red/cyan anaglyph yet, but if you use "crossviewing" (crossing the eyes slightly so that the two images overlap and form a third 3D image) you should be able to see depth in the test image seen below. If you use 3D Camera or any of the other 3D photo apps for iPhone, be sure to send some of your best pics to our Flickr pool: http://www.flickr.com/groups/tuawrigs/pool/

See, now this is the kind of game I want from my iPhone -- the accelerometer isn't just a gimmick thrown in with the gameplay, it's the actual premise of the game. Diorama is a weird little Marble Madness-style maze game, but the catch here is that instead of just tilting the accelerometer to move the ball (which you do), the level of the game actually moves with you, so that you get a stereoscopic kind of effect, as if the stage is real inside your iPhone's screen. Tough to explain, but as soon as you see it above, you'll know what it's like. We've seen this kind of effect before in apps like MotionX's Dice roller, but in this case, it's actually part of the game -- you can only find the paths to take around the stages by actually tilting the device. And for extra 3D viewing, there's an actual 3D mode, so if you happen to have red and cyan glasses around, you can switch on the mode for anaglyphic 3D.

The app is the first iPhone release from a company called Drömsynt, and though the initial reports on iTunes say the game is pretty tough (it is a pain navigating the quickly-moving ball around those pathways), for just 99 cents, it's definitely worth downloading, if only to see how it works. So many apps just throw in a few iPhone-specific features as afterthoughts, but it's refreshing to see a game like this (or like Zen Bound, which really depends on the multitouch screen) rely on the originality of the hardware itself.