Educational 3D and 4D geometry iPhone app

Built an iOS app that teaches what a tesseract is and lets users manipulate it. People keep buying it in a small niche.

At a glance

Estimated by a classifier that read the source. The bar shows how sure it was.

Source

Hacker NewsComment by drewolbrich in “Your best passive income? (2014)”, January 21, 2014

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