Product Designer

Karolis Kosas Portfolio

Product Designer at OpenAI, previously Stripe. His 'Cinema Club' case study — a cross-cinema-chain ticketing app that shipped on the App Store and Google Play — is a clean example of a research insight driving the entire information architecture.

Mobile App DesignInformation ArchitectureUser Research0-to-1

What makes it work

A breakdown of the choices that make this portfolio stand out.

1

One finding drives the core IA decision

A single, clearly-stated research insight becomes the app's two-pathway navigation structure — a clear trace from finding to structural decision.

2

Behavioral detail beyond the obvious

Noticing incidental behavior (screenshotting showtimes to share) led directly to a Favorites and social-sharing feature nobody asked for directly.

3

Named shipped outcome

Confirming the app launched on both major app stores with improved retention is an actual ship date and business-relevant metric category, not just a mockup gallery.

What Product Designers can take from this

Specific, actionable tips to apply to your own portfolio — no generic advice.

  • Distill your research down to one memorable, quotable statistic, then show explicitly how it shaped a structural decision.

  • Look for incidental user behavior in addition to the stated task — it often reveals a feature nobody asked for directly.

  • State what stores/platforms you shipped to and in what timeframe, even without exact numbers.

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