[ehzy]

I mean, I'm not into Lego, but considering what this app does this seems like a pretty fair price. It's doubtless fairly involved to create something like this. It even gives you stylized step by step instruction on how to build then thing it invents for you!

[gnicholas]

According to others, it does not invent the items — these are submitted by users.

Seems like they could run a CourseHero-style business model, where you get access for X months in return for uploading Y creations. Some people would submit junk, but you would get enough good stuff that it would be worth it. Also, you could make the default value for submissions low, but give big bonuses for submissions that reach a certain level of popularity.