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Nikolay
Matorin

Senior Mobile Engineer

Available for work Get in touch

Nine years building mobile apps. Six of them at CHECK24 and Fressnapf, on iOS products used by millions, inside established teams and long-lived codebases. The same work, carried alone, is on the App Store under my own name.

Mobile across both platforms now: Swift and SwiftUI on iOS, and a shared Kotlin Multiplatform core with Jetpack Compose on Android.

See the products
Nikolay Matorin, seated studio portrait in black and white

Experience

Large codebases, real teams, apps people use every day.

  1. Fressnapf, Düsseldorf most recent role, ended March 2026 The main iOS app for Europe's largest pet-supply retailer. Shipped the virtual stamp card, a loyalty feature used across the retail network, working inside the mobile team and its existing conventions.
  2. CHECK24, Cologne Mobilfunk SimOnly, one of Germany's highest-traffic comparison products. Brought the crash rate down and led parts of the UIKit to SwiftUI migration without stopping feature delivery.
  3. iOS and Apple TV, telecom and media Features for an app owned by one of Russia's largest mobile carriers, and the first shipped release of a threat-map startup.
  4. 1C and ERP, St. Petersburg Accounting and logistics systems, the SAP of that market. Real company processes, which is why product constraints do not scare me.

How I work

Two ways to hire me.

Inside a team

What a mobile lead is actually buying: someone who reads an existing codebase before changing it, and leaves it easier to work in than they found it.

  • Works to the codebase, not to my preferencesIn a shared codebase the conventions already in place are usually worth more than my taste.
  • Migrations without stopping deliveryThe UIKit to SwiftUI move at CHECK24 ran alongside the feature roadmap, not instead of it.
  • Review, pairing and hand-overCode other people maintain, and decisions written down so they survive me.
  • Production disciplineCrash budgets, staged rollout, and monitoring that catches problems before support tickets do.
Talk about a role

From idea to store, fast

Give me a product idea and I come back with something people can install. Not a prototype, not a deck: a signed build in a store, with the support page and the privacy policy behind it.

  • Scope cut to a first release, not a wish listThe version that ships is the one that answers a single question well.
  • Architecture chosen for speed that lastsA small unidirectional core and few dependencies, so week six is as quick as week one.
  • Store submission is part of the workListings, screenshots, ratings, phased rollout, and whatever review sends back.
  • Everything the store demands, ready on day oneSupport page, privacy policy, crash monitoring and billing, in English and German.
Talk about a build

Products

Taken from idea to store on my own.

Built, released, supported and maintained without a team behind me.

Live on the App Store

Ironbor

A workout tracker built around the real gym floor. A session lists the exercises and the sets left in each, with the rest timer running in the corner.

About Ironbor
Download Ironbor on the App Store (opens in a new tab)
An Ironbor workout in progress, with each exercise and its remaining sets listed and the rest timer running in the corner

Live on the App Store

LifeSignal

A wellness check-in for the harder stretches. One tap a day to say you are okay, and if a day slips past, the people you chose are quietly told.

About LifeSignal
Download LifeSignal on the App Store (opens in a new tab)
LifeSignal's daily check-in screen

All apps

What I bring

What the nine years add up to.

By the numbers

9years building mobile apps, in production, for other people6of those years at CHECK24 and Fressnapf, on apps used by millions17years in software, counting the ERP work that came before mobile

I care about products that feel native, code that stays readable, and teams that can keep moving after the first release.

Skills

Highlighted is what I use daily; the rest I am fluent in.

Platforms
iOSAndroid
Languages and frameworks
SwiftSwiftUIUIKitKotlin MultiplatformJetpack Compose
Architecture and patterns
Clean ArchitectureSOLIDMVVMTCAComposition
Delivery and production
App Store releaseGoogle Play releaseStoreKitRevenueCatSentryFirebase

Writing

Latest post.

17 July 2026. Architecture, SOLID, Composition.

The architecture behind Ironbor

A codebase usually has its architecture settled long before you arrive in it, and the pattern debate rarely settles the underlying problem: the weight moves from the view controllers to the view models. For my own app I started from principles rather than a pattern — SOLID, composition, small modules — and ended up with a small unidirectional core and almost no dependencies.

Read the post

All posts

Outside the job

A bit about me.

I moved to Germany in 2020 and became a citizen in 2025. English is my working language, Russian my first, and German the newest of the three: B1 certified, and now taking the B2 Beruf course that gave Wortschatzi its vocabulary.

Sport takes most of what is left: the gym four or five times a week, and badminton every two weeks.

I am part of International LGBTQ+ Düsseldorf (opens in a new tab) .

Together with Shameel Faraz (opens in a new tab) I develop and maintain the DüsselQueers app (opens in a new tab) for our community, from its design to every App Store release, which I publish from my own account.

Contact

Full-time, remote, or contract.

Available
Now (as of August 2026)
Based in
Düsseldorf, Germany
Time zone
CET, UTC+1
Work permit
German citizen, no sponsorship needed
Send a message

I answer within a working day. Tell me the platform, the timeline, and whether it is a role or a build.

Or email hello@bobkexit.dev . Also on LinkedIn (opens in a new tab) and GitHub (opens in a new tab) .