Web design & app development in Köln
Websites & apps forKöln.
I'm Marvin Hülsmann – web designer and Apple developer from Berlin. I design and build websites, landing pages and native apps for companies, freelancers and startups in Köln and across Nordrhein-Westfalen.
Cologne thrives on media, trade fairs and an open, direct manner – which matches the way I work. Whether a startup in Ehrenfeld or a family business nearby: I build things that feel right.
Free intro call- Based in
- Berlin, remote for Köln
- Reply
- within 24 hours
- Apps on the App Store
- 3
- Stack
- Next.js · React · Swift · SwiftUI
Services
What I build for Köln.
Web design & websites
Custom, responsive websites with Next.js and Tailwind – fast, accessible and optimised for Google. No page builder, no template.
App development for Apple
Native apps for iPhone, iPad, Apple Watch and Vision Pro in Swift and SwiftUI – from concept to release on the App Store.
SEO & local visibility
Technical search engine optimisation, structured data and performance so customers from Köln find you on Google.
Consulting & support
Honest advice, clear quotes and support after launch. You always talk to me directly – no agency loops.
Why me
Personal instead of agency.
Working together
From Berlin – for Köln.
Most of my projects run fully remote: video calls, a shared design board, transparent updates. For a kick-off or workshop I'm happy to come to Köln in person.
One contact
Design, development and support from one person. Short paths, fast answers.
Apple developer
Several of my own apps on the App Store – for iOS, watchOS and visionOS. I know how products get finished.
Fair & transparent
Fixed quotes without hidden costs. You always know what you get.
Attention to detail
Typography, motion, load time – I build things that feel as good as they look.
Process
How we work together.
Intro call
We talk for 30 minutes about your idea, goals and budget. Free and without obligation.
Concept & design
Structure, content and a design that fits your brand – before a single line of code is written.
Development
Clean implementation with a modern stack, live preview links and quick feedback rounds.
Launch & support
Release, search engine setup and support afterwards. I stay reachable.
FAQ
Common questions from Köln.
Do you also work on site in Köln?+
Yes. Most collaboration happens remotely via video call, but for a kick-off, workshop or photos I'm happy to come to Köln. I'm based in Berlin.
How much does a website in Köln cost?+
It depends on scope and features. After a free intro call you get a fixed quote without hidden costs – for a landing page as well as for a multilingual company site.
How long does a project take?+
A landing page goes live within days, a complete website usually takes two to four weeks. Native apps take several weeks to months depending on scope. You see progress continuously.
Do you also build apps for companies in Köln?+
Yes. I build native apps for iPhone, iPad, Apple Watch and Vision Pro in Swift and SwiftUI and guide you all the way to the App Store release.
Will my website be found on Google?+
Every website gets a clean technical foundation: fast load times, structured data, correct meta tags and mobile-first. Local visibility in Köln is part of the plan from day one.
Also near Köln
I work with businesses across Nordrhein-Westfalen and all of Germany.
Next step
Ready for your project in Köln?
Tell me briefly what it's about – I'll get back to you within 24 hours.
Write an email
Free intro call