I have been a math geek since I was four years old (Eisenhower, the last great, or even good, Republican president was still in his first term) and I became an amateur topologist and horologist not long after. This app not only makes an extremely obtuse and non intuitive topic accessible, it also manages to make it enjoyable and...dare I say it: FUN ! I have shared this app with my nephews and nieces AND their children (some as young as 5 years old) and it has always elicited excitement, curiosity and many, many questions. It will be interesting to see how their very early exposure to easily accessible and yet extremely abstract concepts affects their abilities to process and assimilate abstract and obtuse ideas going forward (or, in this instance, rotating outward and folding up...). I do, however, have one suggestion...although the two pages where you ‘hack’ the optic chiasma (meld two images into a “3-D” facsimile) work fine on my iPhone and my iPad Mini they don’t do well on standard sized iPads. My arms, and I’m 6’4” tall, are too short to hold the screen far enough away to fix and hold the images in place while manipulating the conjoined image. If you were to make an iPad-friendly version of those two pages, one in which they are just a little bit closer together, it would vastly improve the experience.

Now I understand why Dali painted the hypercube the way he did. I had a poster print of that painting on my wall 45 years ago, but wound up studying language instead of math. I’m still a math geek in my spare time, but for some reason I’d never gotten around to trying to manipulate a hypercube in 3 dimensions. I would say my education is complete, but it never will be, of course. But thanks for filling in this part—I’ll be seeing how many odd 3-D shadows I can make from this. And wondering about representing five dimensions in three. Since, after all, this 3-D tesseract is only really projected onto my 2-D iPad screen, so both the third and fourth dimensions are illusions of perspective.

I love this app so much. I may not use it every day, but I do use it often. It is so hard (potentially impossible even) to contemplate what a 4 dimensional object is and how it behaves. This app has been a godsend to me because it never fails to stimulate my brain in both curiosity and fascination. Highly recommend, and don’t just go through the process once. Repeat it, and marvel in it, and then after some time has passed repeat the process, and after a few times you will be blown away when you start to grasp the impossible. Thank you Devs!!!

I've been reading about the fourth dimension for decades, but never understood or pictured it as well as I do now thanks to this ingenious app. It really deserves to be better known and more widely appreciated. It makes brilliant use of both the iPad's ability to show animation and its multi-touch interface.I hope the developer will consider extending the app to cover other 4D shapes. He's also made himself the obvious person to create an interactive version of Abbot's classic, FLATLAND.In the meantime, get this app, and break through the walls of mere 3D perception. If this topic interests you at all, you won't regret it.