Native engineering
High-performance iOS and macOS apps built with modern Swift Concurrency and clean, testable architecture. The person you brief writes the code; nothing gets handed off.
Senior iOS engineering and app care
One Senior Engineer. Zero Hand‑Offs.
I'm John Durcan. I design, build and maintain native Apple apps, and I've shipped six of my own end to end: the code, the App Store listings, the websites and the support inbox. Itch.studio puts that whole-lifecycle experience to work on your app.
Featured product
TimerStack.app
How I work
Product thinking, interface craft and long-term support.
Product strategy
Native app design
SwiftUI engineering
Applied AI features
App Health Checks
Maintenance care
Product strategy
Native app design
SwiftUI engineering
Applied AI features
App Health Checks
Maintenance care
What I do
Take an app from idea to the App Store, then keep it healthy once real users show up.
Deep ecosystem integration
Complex native frameworks put to real use across my own apps: HealthKit, MusicKit, CoreBluetooth, on-device ML and production AI integrations, including private options for data that cannot leave the building.
Post-launch care
Apple moves every year. I keep shipped apps ready for new iOS releases, App Store policy changes and SDK deadlines, so launch day is a beginning rather than a cliff.
Selected work
Six apps designed, built and shipped solo. Live products with real releases and real users, not case studies.
Flagship product
TimerStack
TimerStack shows the whole practice in one place: product strategy, native app craft, a supporting website and a visual system that stays coherent across every touchpoint.
- Routine timing experience designed to feel focused, calm and precise
- Website and app presentation aligned as one consistent product
- Built through real release and iteration work, not a speculative case study
Pool care product
AuraPool
A reactive pool-chemistry app where the water responds to your readings in real time, with exact chemical doses, safe step-by-step treatments and weather-smart recommendations.
View project
Design tooling
UI Color Palette Designer
A complete interface palette from two sliders, generated in OKLCH, graded against WCAG as you drag and simulated through four kinds of colour vision deficiency before you ship it.
View project
Creative AI product
PoeticAI
A compact AI product that shows how even smaller app ideas can ship with a clear concept, strong UI judgement and production discipline.
View project
Pet behaviour product
Bark Back
A real-time audio product that listens for a dog's bark, answers it with its own bark and films the reaction, helping owners understand their dog's behaviour with an honest way to measure whether it works.
View project
Diagnostics utility
bluetooth.itch
A technical utility shaped by real Bluetooth workflows, where usefulness, speed and technical clarity matter more than feature theatre.
View project
Who you hire
John Durcan
Senior iOS engineer, based in Farnham, England. Production experience from fintech at OANDA, where I led a migration from legacy UIKit to SwiftUI on live crypto trading apps, and App Store work for more than fifteen international clients before that.
Before engineering I spent twelve years co-founding and running a marketing agency of more than twenty people. That is the part of my background that shows up in the apps: scoping, deciding what not to build, and getting things finished.
Itch Studio Ltd is the wrapper for contracts and invoicing. The work itself is one senior engineer, start to finish.
Approach
Clarify the product, build it cleanly, then stay close enough to improve it properly.
Shape the scope
Work out what matters now, what should wait, and where product complexity actually earns its place.
Design for implementation
Use real UI constraints, platform behaviour and content hierarchy from the start rather than decorating in hindsight.
Modern tooling, honest velocity
Agentic AI runs through my own development pipelines to clear boilerplate and busywork, so paid senior time goes on product decisions rather than plumbing. The saving lands in your budget, not an agency's margin.
Start here
The iOS App Health Check. Know exactly where your app stands, in one week.
A fixed-price audit for anyone with a live iOS app and no iOS engineer looking after it. You get a clear, prioritised report your team owns either way; if you want the fixes handled, it maps straight onto a care plan below.
What the week covers
- SDK, dependency and deprecation risk against Apple's current deadlines
- Crash and performance review of the shipping build
- App Store compliance and policy exposure
- Accessibility review against Apple's guidelines
- A prioritised fix list your team owns, whoever does the work
£950 fixed, one week
Care plans
Monthly care for shipped apps, from an engineer who ships his own.
Launching is the start, not the finish. New iOS releases, App Store policy changes and SDK deadlines arrive on Apple's schedule, whether or not anyone is looking after your app. These plans make sure someone senior is.
Essential care
For stable apps that need compatibility, oversight and a reliable owner.
From £950/month
- 4 hours of changes each month
- iOS and iPadOS release readiness checks
- SDK, dependency and App Store policy review
- Minor bug fixing and submission support
Product care
For live products that need regular iteration, polish and operational follow-through.
From £2,200/month
- 12 hours of changes each month
- Small UX refinements and release support
- Accessibility review and remediation work
- Localisation upkeep for existing screens and strings
Studio partner
For teams that want an ongoing product, design and engineering partner.
From £3,800/month
- 24 hours of changes each month
- Priority turnaround and monthly planning
- Deeper product review across roadmap and releases
- Coordination with your wider team when needed
What these plans cover
Compatibility work for new Apple OS releases, HIG and accessibility alignment, App Store compliance, localisation maintenance, release preparation and the steady product clean-up that shipped apps always need.
What gets scoped separately
Major new features, backend rebuilds, full redesigns, large-scale localisation projects and urgent out-of-hours work sit outside the monthly allocation and are quoted separately.
Contact
If your app needs strong product judgement, clean execution and support after launch, let's talk.
I work from the UK with founders and teams who want their Apple-focused apps looked after properly, whether that starts with a Health Check, a new build or an ongoing care plan. You deal with me directly, from first call to every release.