Mobile App
Development

We build mobile apps that ship to the App Store and Google Play, and keep working after they get there.

We build cross-platform. One codebase, both stores, one team maintaining it. That is a deliberate choice rather than a limitation. It means the two versions of your app behave the same way, fixes land on both at once, and you are not funding two separate builds of the same product.

Some of the work is the visible part. Screens, flows, the things a user touches. Most of what decides whether an app succeeds sits underneath: what happens when the connection drops, how data gets back in sync, how it behaves on a five year old handset, what breaks when the platform rules change in September.

What We Build

Not every project needs all of this. These are the parts we go deep on when a product calls for them.

  • Cross-platform apps

    React Native, one codebase running on iOS and Android. We follow each platform’s conventions where users expect them, so the app still feels like an iPhone app on an iPhone.

  • Offline first and sync

    Apps that keep working without a connection and reconcile cleanly when it comes back. We build this as a proper data layer with server side authority over conflicts, not a cache added at the end. If your users work in the field, on sites, in the air or anywhere with patchy signal, this is the part that decides whether the app gets used.

  • Accounts and access

    OAuth and JWT, secure credential storage on the device, guest and anonymous modes, and role based access where different kinds of user need different views of the same product. We have built one account working across two separate apps in the stores, sharing a single backend.

  • Backend and integration

    Most mobile work talks to something that already exists. We integrate with what you have, or build the server side too. That is backend and API development.

  • Accessibility

    Screen reader support, keyboard and switch navigation, contrast and touch target sizing, tested against WCAG 2.1 AA. We scope this as real work with real hours against it, because that is what it is.

  • Release and store handling

    Signing, store listings, review submissions, staged rollouts, and the resubmissions that follow each OS release.

  • Testing

    Automated end to end coverage plus manual testing on a real device range, not one current flagship.

When Teams
Come to Us

  • A first app, and
    no mobile team
    in house

    You have a web product or a business that needs an app, and hiring a mobile team for one project makes no sense. We take it from scoping through to store.

  • The app has
    to work
    offline

    Field work, travel, sites with no signal. This is the request we get most often that other agencies treat as an afterthought.

  • A second app
    off the back of
    the first

    A spin-off aimed at a different audience, sharing a backend and a single login across both. We have done exactly this: one product line, two apps in the stores, one account.

  • An app that already
    ships and needs to
    keep shipping

    OS updates, deprecated libraries, store policy changes. Apps rot if nobody maintains them.

    See

  • An app
    someone
    else built

    An inherited codebase with no documentation and no original developer. We audit before committing to anything.

    See

Do You Have a Project Idea?

Our technical experts and business analysts will tell you how to transform your idea into a fully-fledged digital product with the help of website design and development services.

Let’s Discuss

How We Work

Goals, users, constraints. The output is a scope you can price and argue with.

Flows, then screens, then a prototype you can hold on a phone before anything gets built. See mobile app design.

Sprints, with something running at the end of each one.

Automated and manual, across a device matrix.

Store submission, review, staged rollout.

Every project includes one month of bug fixing after launch at no extra cost.

Stack

  • Cross-platform: React Native, Flutter
  • Backend: PHP with Laravel, Node.js, NestJS, Python with Django
  • Data and Sync: Offline first local storage with event based sync
  • Auth: OAuth 2.0, JWT, platform secure storage, Supabase, Firebase Auth
  • Testing: Playwright for end to end, manual device testing
  • Delivery: CI pipelines, staged rollout, crash and performance monitoring

Performance and Quality

We set numeric targets during scoping and test against them, rather than describing the app as fast and hoping.

On a recent project those targets were a three second cold launch, sustained 60fps in the interactive views, and a memory ceiling under load. Yours will be different. The point is that they exist, they are written into the estimate, and QA checks them before release.

Accessibility works the same way. WCAG 2.1 AA is a line in our estimates, not an aspiration.

Selected Work

  • Duo. Consumer app for scheduling dates through professional planners. Live in both stores
  • Vision Care Patient Platform. Patient app for managing a course of eye care, with separate patient and practitioner roles. Later extended into a second wellness app sharing the same backend and the same accounts.
  • Therapist and Client Engagement App. Cross-platform mental health app connecting therapists with their clients, with guided exercises and between-session tracking.
See All Work

Industries We Build For

Healthcare and wellness is where we have gone deepest on mobile, with four shipped apps. We also build for booking and scheduling platforms, and travel and mobility.

How We
Work Together

  • Fixed scope

    A defined build, priced per module, with a timeline. Suits a clear brief.

  • Ongoing team

    Developers, QA and design working to your roadmap. Suits products that will keep changing.

  • Support retainer

    After the first month of free bug fixing runs out. See
    A typical MVP runs with two developers, a QA engineer and a designer. Larger builds scale from there.
    We price every project individually. There are no packages, because the work does not arrive in packages.

Questions We
Get Asked

  • We build cross-platform, in React Native. One codebase for both stores, one team maintaining it, and both versions behaving the same way. For most products that is the right answer and a cheaper one. If your app depends on something only a native build can do, we will tell you that during scoping rather than after you have signed.

  • We give you a rough estimate as soon as we understand what you want to build. That is usually enough to know whether the project is worth taking further.

    The detailed number comes after we have agreed the scope with you, once the goals and the functionality are settled. At that point we break the estimate into modules and price each one, so you can see what an offline data layer or a video player actually costs and decide what belongs in version one.

  • A small, well defined app runs around twelve weeks. A larger build with offline sync, media handling or several user roles runs eight to ten months. Both of those are real numbers from recent projects rather than brackets.

  • Yes. Most of our mobile work integrates with something that already exists.

  • Every project includes one month of bug fixing at no extra cost. After that, ongoing work runs as a support retainer with agreed response times. See application support.

  • Yes, starting with an audit. See project takeover and modernisation.

Related Services

Let’s talk about your project

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