Mobile Development

Mobile apps, shipped to both stores

React Native and Flutter when one codebase makes sense, Swift and Kotlin when it doesn't. We build, release and maintain apps for iOS and Android, including the backend behind them.

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15+
Years of experience
EU & US
Markets served
Senior only
No juniors on projects
AI+
Accelerated delivery
The problem

Where mobile projects go wrong

Mobile punishes shortcuts more than web: users rate you publicly, and every crash has a star rating attached.

Two platforms, one budget

iOS and Android as separate native projects doubles the cost and splits the team. Cross-platform fixes that, but only when it fits the app you're building.

The app exists, the reviews hurt

It crashes on certain devices, drains battery, and sits at 2.8 stars. The team that built it is gone, and the SDKs are three versions behind.

Your field teams still use paper

Technicians, drivers and warehouse staff work where the connectivity is worst. They need offline-first apps, not a responsive website.
What we do

Build, rescue, maintain

One team for the app and its backend, so nothing falls between two vendors.

Cross-platform development

React Native or Flutter, one codebase for both stores. Right for most business apps, and we'll tell you when it isn't.

Native development

Swift and Kotlin when performance, hardware access or platform features demand it: payments, sensors, background processing, wearables.

App rescue and modernization

We take over existing apps, fix crash rates, update SDKs and dependencies, and get you back to passing store reviews without a rewrite.

Offline-first field apps

Checklists, photos, signatures and sync for people who work without coverage. The app works in a basement, and the data reconciles when it's back online.

Backend for mobile

APIs, push notifications, auth, offline sync. Built alongside the app, so the contract between them never becomes a finger-pointing exercise.

Release and store management

CI/CD for mobile, TestFlight and internal testing tracks, phased rollouts, store review handling. Releasing stops being a monthly adventure.
The stack we work with
React NativeFlutterSwiftKotlinFirebaseOffline-first syncApp Store / Play CI/CD
Case study
−40%
time per job after the offline-first field app

Field service company, technician app

Two hundred technicians filled paper protocols and drove them to the office weekly. We built an offline-first Flutter app: checklists, photos, client signatures, background sync. It works in basements and elevators, and the planning system gets the data the moment the technician is back in coverage. Average time per job dropped 40%.

FlutterOffline-first200 field users
How it works

From discovery to the stores

You test the real app on your phone every week, from the first sprint.

01

Discovery

Users, devices, offline requirements, store constraints. The platform decision (native vs cross-platform) comes out of this, with reasons.
02

Design and prototype

Clickable prototype on real devices before full development. Cheap to change here, expensive later. UX/UI design is part of the project, not a separate order.
03

Weekly builds

Installable builds on your phone every week via TestFlight and internal tracks. You feel the app, not read about it.
04

Release and monitoring

Store submission, phased rollout, crash and performance monitoring. We watch the first weeks in production, not just the launch day.
Outcomes

What you get

  • One team for iOS, Android and the backend
  • Weekly builds you can install and test
  • Crash-free rate above 99.5% as the working standard
  • Store releases without drama
“Our technicians are not tech people. They picked the app up in a day, and we stopped chasing paperwork.”
Thomas Berg Operations Director, facility services
FAQ

Common questions

Native or cross-platform?

For most business apps: cross-platform, one codebase, 30-40% lower cost. Native wins when you need heavy hardware access, top-end performance or deep platform integration. We recommend per project and show the reasoning.

Can you fix our existing app?

Usually yes, without a rewrite. We start with a crash and dependency audit, stabilize the worst offenders, then modernize in steps.

Do you handle store publishing?

Yes, including review rejections, privacy declarations and phased rollouts. It's part of the delivery, not your homework.

What about the backend?

We build or extend it as part of the project. Push, sync, auth and APIs are designed together with the app, by the same team.

Planning an app, or stuck with one?

Tell us what the app should do, or send a link to the one that needs help. Concrete plan and price within days.

Talk about your app
or write to us directly: hello@udb.pl