fonszi
A cross-platform product studio focused on Kotlin Multiplatform and Compose. All from a shared codebase that runs natively on every platform.
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We architect, build, and deploy high-performance iOS, Android, and full-stack systems for venture-backed startups and enterprise platforms.
Track, time, and design
We don't sell theory. These are production applications built, deployed, and managed end-to-end by the studio. Tap into the design details to audit our quality.
fonskii - Ski Tracker
Altitude, speed, and vertical on every run. Auto-detects 6,851+ resorts worldwide, 38 languages.
BeLoop - Workout Timer
Six timer modes for any workout. Tabata, EMOM, AMRAP, Interval, Countdown, Stopwatch. Now on Apple Watch and Wear OS. Zero excuses
The studio standard
We move fast. We move right. We don't compromise on either.
One codebase. Every platform
With Kotlin Multiplatform we ship fully native iOS, Android, watch, web, and desktop from a single codebase. Half the maintenance, twice the velocity, zero compromise on native feel.
Beyond the screen
Most apps stop at the glass. Ours reach the physical world - sensors, wearables, and connected hardware, streaming real-time data reliably. It's the hard part most studios quietly avoid, and the part we specialize in.
AI experts - not AI tourists
Most teams are still reading the docs. We ship our own AI products and wire production-grade AI into client apps - the kind that holds up with real users and real edge cases. We live on the frontier so your product ships there first.
Used by the world's leading companies
"fonszi" means something like "buddy" or "close friend", and that's the energy we bring to every project: fully in your corner.
Built by engineers who ship
fonszi was founded on a simple principle: great products require great engineering. We've spent years building systems that scale, teams that perform, and companies that matter. This is what we know.
Let's build something real
Share your scope, stack, and timeline. We'll move from there.