SERVICES / BUILD & DESIGN · MOBILE APP DEVELOPMENT

Mobile App Development

We build mobile apps that reach both stores and stay there — native Swift and Kotlin where the product demands it, Flutter or React Native where one codebase earns its keep. The record includes the Qatar Ministry of Foreign Affairs’ official Flutter app, live in production on iOS and Android, and a native iOS + Android build for a US SaaS taken to mass adoption.

The free 30-minute session gives you an honest native-vs-cross-platform read for your specific product, plus a realistic store-to-store plan. You keep the notes either way.

Qatar Ministry of Foreign Affairs mobile app built in Flutter, live on iOS and Android
Qatar MoFA · Flutter, live in production
01Found in the field

The mobile decisions that hurt later

N-01

Native or cross-platform, decided by whoever answered first

The most expensive mobile decision is usually made in the first sales call, by the vendor’s staffing convenience. The honest answer depends on your product: camera and sensor depth, animation load, team you will hire later. We give that answer in writing before any commitment.

N-02

The app exists; the releases stopped

An app in the stores with a two-year-old build, failing on new OS versions, built by a vendor who moved on. Store requirements move constantly — an unmaintained app is a slowly closing door.

N-03

Two platforms, two codebases, one budget

An iOS contractor and an Android contractor, drifting apart feature by feature. Half your budget goes to keeping them identical. This is exactly the case where cross-platform pays — and where an honest vendor says so.

N-04

The backend was an afterthought

Mobile apps fail in reviews for backend reasons: slow APIs, broken sync, lost sessions. An app is a distributed system with a pocket-sized front end — it needs a team that owns both halves.

Two of the Fluvius team in Central Park, New York, between client sessions
Client work · New York
On-site when it matters

The native app that reached mass adoption was built shoulder to shoulder with the client — New York sessions included.

02Deliverables, not adjectives

What you get

Native iOS and Android

Swift and Kotlin where the product needs the metal: deep camera work, AR, background processing, platform-specific polish. Our native record includes a US SaaS companion app taken to mass adoption on both stores.

You get: native apps with platform-idiomatic UX, shipped to both stores.

Cross-platform where it earns its cost

Flutter and React Native for products where one codebase covers both stores honestly — the Qatar MoFA app is Flutter, in production as a national government service.

You get: one codebase, two stores, and a written justification for the choice.

The backend behind the app

APIs, sync, push, auth and analytics designed with the app, not bolted on — one team owns the whole loop.

You get: a backend built for mobile realities: flaky networks, background limits, store review rules.

Store delivery and life after launch

Store submissions, review cycles, crash monitoring, OS-version upkeep — the operational half of mobile that determines whether the app is alive in year two.

You get: apps that pass review and keep passing it, release after release.

03The path, with dates

How it works

STEP 01

Platform decision, in writing

Native vs cross-platform argued against your product’s real requirements — sensors, animation, offline, hiring plans — with the reasoning documented.

week 1
STEP 02

Design and architecture

Screens, flows and the API contract designed together; a senior architect signs the system design before development.

weeks 2–3
STEP 03

Build to TestFlight and internal track

Working builds in your hands every week — real devices, real data, weekly demos.

weeks 4–10
STEP 04

Store launch and upkeep

Submission, review, launch on both stores, then monitoring, crash triage and OS-version maintenance on a monthly model.

ongoing
Two of the Fluvius team at a client's office in New York, brick buildings through the window behind them
At the client’s office · New York

Real devices, real networks, before review does it for you.

Fluvius visiting Westfield in London, a UX client
Westfield · London
Polish is a requirement

Mobile users forgive nothing. The polish bar we learned on brand work applies to every screen we ship.

05Book a call

Get the platform answer before the budget

One 30-minute session with an engineer: your product, an honest native-vs-cross-platform read, and the shape of a first fixed-scope phase — design plus a working first build. Plan and price in writing before you commit.

Have an existing app that stopped shipping? The first phase is a short audit of the codebase and store status — findings in writing.

Store-grade, always

A store review is an audit you cannot argue with. We build to pass it on the first try — and keep passing it every OS cycle.

Production standard · 60 seconds
07Asked before buying

The questions buyers actually ask

Native or cross-platform — how do you decide?

Against your product, not our staffing: sensor and camera depth, animation load, offline needs, the team you plan to hire later. Flutter carried a government app to production for us; native carried a consumer SaaS to mass adoption. The recommendation comes in writing with the reasoning attached.

Do you handle the app store submissions?

Yes — both stores, including review cycles, rejections and the metadata work. Apps are published under your accounts, in your name, like everything else we build.

Can you take over an app another team built?

Yes — audit first: codebase, backend, store status, crash data. Findings and a stabilisation plan in writing, then releases restart. If it is a full rescue, our Product Rescue service is the dedicated door.

Do you build the backend too?

Always, or we integrate carefully with yours. Most mobile failures are backend failures wearing an app costume — sync, sessions, slow APIs — so one team owning both halves is a quality decision, not an upsell.

How long does an app take to ship?

A focused first version typically reaches TestFlight in six to ten weeks and the stores shortly after review. The written plan gives dates for your scope specifically.

What happens after launch?

Monitoring, crash triage, OS-version upkeep and feature development on a monthly model. Store platforms move constantly; an app needs an owner, and we stay on as one for as long as it earns it.

GATED ONE-PAGER · PDF

Seven ways to get software built well — the one-page version

The Build & Design services on one printable page: what each covers, when it is the right door, and what the first deliverable looks like. Built to be forwarded to whoever holds the budget.

No company field, no phone. Free and disposable email domains are filtered; the download appears right here once the address clears.

08The next 30 minutes

Your app, on both stores, maintained

Book the free 30-minute session for the honest platform answer and a store-to-store plan — or write two sentences about the app you need, and an engineer replies in one business day.

  • 30 minutes, an engineer on the call
  • You keep the written notes either way
  • Nobody follows up more than once
PREFER TO WRITE FIRST?REPLY IN 1 BUSINESS DAY

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