Etienne Noumen

iQz - Reasoning Puzzles

I built a puzzle app because I noticed I was getting worse at thinking.

Not dramatically. Just — I'd reach for a model before I'd reach for the problem. Draft the email, summarise the doc, sanity-check the logic. All reasonable. All things I used to do myself.

The puzzle in the video takes about five seconds. Count across each row: one, two, three. The shape stays constant down the row. So the missing tile is three pentagons.

That narrows it to two options, and this is the part I find interesting: most people pick the solid one. The count rule is satisfied, the brain files it as solved, and it stops looking. The correct tile is the outlined one — matching the row it belongs to. Find a rule that fits, stop checking. It's a small failure, and it's the same shape as the big one.

So I built iQz. 65 reasoning puzzles — matrices, sequences, number series, verbal analogies, logical deduction. Every answer explains the underlying rule rather than just showing you the letter, because the point isn't the score.

It's free, works fully offline, and has no ads and no account. I built it for my own commute.

Two honest caveats. It won't measure your IQ; that isn't what this is. And I'm well aware of the irony of shipping an app about unaided reasoning while running a company that builds AI study tools. Both things are true. The tools are useful, and the skill is worth keeping anyway.

• 65 reasoning and logic puzzles
• Fully offline and local
• Zero ads, no account required

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• Figures from Black history
• iPhone, iPad and Mac