Klaus Custom Studio · Seaside, California

One developer.
Real apps.
Shipped.

KCS is a solo studio out of Seaside, CA. I build Flutter mobile apps and web products from idea to App Store — designed, coded, and launched by one person who actually gives a damn about the work.

By the Numbers
3
Apps in the market
QR Party, RollCall, Wrench Market — all built solo from concept to launch.
iOS
+ Android. Both stores.
App Store submissions, TestFlight, Google Play — testers welcome on both platforms.
0
Agencies involved
No middlemen. No account managers. Just the developer who built it.

The Work

// Three Active Apps
QP
Launching June 1
QR Party
Event RSVP and check-in via QR code. Real-time guest lists, instant access. Zero paper.
Flutter · Firebase · iOS + Android
WM
In Development
Wrench Market
On-demand mobile mechanic marketplace. Verified techs. Escrow payments. They come to you.
Flutter · Firebase · Stripe · Plaid · Claude API
RC
Coming Soon
RollCall
OHV ride coordination with real-time GPS tracking and trail maps. Built for dirt.
Flutter · Supabase · Mapbox · Firebase · FCM
// Work Together

Have an
idea?
Let's build it.

You don't need a big team. You don't need an agency. You need someone who can take an idea from a napkin sketch to the App Store — and actually give a damn about how it turns out.

Bring the vision. I'll handle the rest — architecture, design, development, deployment. All of it.

Find Me on Upwork ↗
What I can build for you
  • iOS + Android apps — Flutter, shipped to both stores
  • Web products — Next.js, fast, scalable, production-ready
  • Backends + databases — Supabase, Firebase, real-time ready
  • AI-powered features — Claude API integration, chat, vision, search
  • Payments + marketplaces — Stripe Connect, escrow, subscriptions
  • Maps + location — Mapbox, GPS tracking, geofencing
Flutter · Dart · Next.js · TypeScript
Supabase · Firebase · Stripe · Claude API · Mapbox
Studio
Philosophy

"No agencies. No account managers.
No one who touches your project
but never sees the code.
Just the person who built it."

KCS is one developer in Seaside, CA who rides dirt bikes, wraps his kids' birthday presents, and builds apps that solve real problems. Every pixel, every function, every deployment — owned completely. That's the deal.

Let's build
something.

Freelance inquiries, product partnerships, or just want to talk shop — reach out directly. No forms, no bots.

Direct Line
admin@klauscustom.com
Klaus Custom Studio LLC
Seaside, California
D-U-N-S 145012101