The app icon is irresistible.

Thanks. It was essentially my son's idea (age 5 at the time), and it was about a month after I designed the icon that I realized the "third eye" connection, as in http://en.wikipedia.org/wiki/Third_eye which made me love it even more.

I'm really looking forward to your next iOS app, Fiasco -- it looks awesome. I hope you don't get sued for Scrabble kicking Tetris in the face, or by Stanslaw Lem's estate!

From the reviews, it sounds like the high quality of your explanations has made a small geeky niche far less small, geeky and niche. Bravo.

Heard about this app when it first launched, such an original idea.

Would you feel comfortable telling us the number of sales in 2013?

The Fourth Dimension generated $17,600 during 2012, the year I launched it. The majority of that was driven by reviews the app got.

In 2013 it made $3900, or $325/month, and seems to be holding at that rate of income. The only work I did on the app in 2013 was about two days making it work correctly on iOS 7.

It's not huge money, but it's far more than my expectations, which were on the order of $500 total over the lifetime of the app.

I posted a breakdown of the first three months of reviews here: http://www.fourthdimensionapp.com/first_three_months/

My next app is a two-player Tetris/Scrabble mashup: http://fiascoapp.com/b

My expectations for the word puzzle game are either $300,000, or zero. The wave function has yet to collapse.

Seems to violate the premise of "the dumber the app, the more popular it will be." Awesome.

"The dumber the app..." works almost everytime. I launched a conceptually great app which was a complete failure: https://itunes.apple.com/in/app/gravity-byte/id504372023?mt=...

Then launched a card game which is a decent success..

Gravity Byte may be a great app. But, it does not make a great first impression. You may want to try to give the app a more cohesive art direction. For example, in the app screenshots, I see 4 different fonts. Also, the game graphics don't really grab my attention. Keep in mind that most people are judging your app almost entirely by the screenshots.

You could probably turn that around rather easily by paying a good designer or graphic artist to produce some professional looking assets and reskinning the game.

It's a shame, the icon for Gravity Byte looks really nice, but then the screenshots put me off instantly.

Wish you had an Android version :/

Kudos anyway, great idea and looks like a great execution as well!

Cool! My mom showed this to me (she's a maths teacher) In fact it was the first app she ever bought! She just loves showing it to all her science colleagues! That really is an awesome app!

I love hearing stories like that, thanks. I never thought it would resonate with so many people.

Nice! WRT to the icon, you should add stereoscopic imaging (red/green style) to geek out even further!

Near the end of the app, there is a cross-eyed stereo viewing mode that works pretty well, although it can be headache inducing for some people.

That looks so cool. I'm glad it brings in a good amount of money.

I just bought a copy myself!