Jakub Sledz, product designer

Jakub Sledz, product designer. Apps and websites designed end to end: Pogaduszki, Kinguin Expeditions, Fit Check, Habituu, Precigeon.

I'm Jakub. I design apps and websites end to end, then I stay for the numbers.

I count a project as done when the numbers move, not when it ships.

Talk to people, build something they can hold, keep a receipt for every claim.

scroll for the work

Case study 01View case study

Pogaduszki

1,200+ childrenShipped as Linghos2022-25
→

Daily speech therapy, disguised as a game a four-year-old asks to play.

0 to 1 · Co-founder · iOS & Android · Web platform · 2022-25

Case study 02View case study

Kinguin Expeditions

Design leadPiloted in 4 markets2022
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Loyalty built as a game, so players got paid in play instead of coupons.

Marketplace web · Loyalty loop · Expeditions & Krowns · 2022

Case study 03View case study

Fit Check

Concept for ZalandoLive demo inside2026
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Every morning, a deck of looks on your own body, one swipe from the cart.

Concept for Zalando · Prototype-tested · iOS & Android · 2026

Case study 04View case study

Habituu

Concept, iOSReal pairs, 30 days2026
→

A habit app that hands you a person, not a checkbox.

Self-directed · Core loop run live for a month · iOS · 2026

Case study 05View case study

Precigeon

MVP live10-store pilot2026 · ongoing
→

The scanner that shows a store owner what ChatGPT says about them.

B2B SaaS · Live at precigeon.com · 2026, ongoing
About

I'm a product designer who builds, from the first interview to the numbers after launch.

Most of these started with talking to the people who would use the thing, turned into a prototype I could put in someone's hands, and ended with numbers that said whether it worked. I wrote down what happened at every step, which is why the case studies are long.

I build prototypes in code when that answers the question faster than Figma would, usually with AI helping me write it. And I leave a team's design system tidier than I found it.

Jakub Sledz
Research → strategy → UI → ship → measurepractice
iOS, Android, responsive webplatforms
Figma, code prototypes, AI copilots, analyticstools
Europe (CET) · remote worldwide · open for workbased
Tell me about the next one →

to be continued.