Rubicon Creators
Estimate project

Remote mobile studio

Past the point of prototypes.

WebuildiOSandAndroidproductsforteamswho'vealreadydecided.Teamextensionwhenyouneedspeed,full-cycledeliverywhenyouneedownership.

Estimate projectSee our work

Availability

Two delivery slots open for Q4 2026

  • Halden4.8· App StoreiOS + Android
  • Cadence Health4.9· App StoreiOS
  • Terrafleet4.6· Google PlayAndroid
  • Nook Ledger4.7· App StoreiOS + Android
Downloads shipped
2.4MAcross 19 released products
Average store rating
4.8Weighted by install base
Raised by clients post-launch
$46MSeed through Series B
Crash-free sessions
99.7%Trailing 90 days, p95

Selected work

Three shipped products.

Every one of these had a version that did not ship first. Problem, what we changed, and what it moved — with the numbers.
Halden — illustrative app screen

Fintech · iOS + Android

Halden

A Nordic savings app that had to feel like a bank and move like a startup

Problem

A React Native prototype passed demo day and then stalled: 11-second cold start, and compliance blocked launch over data leaving the device.

Approach

Rebuilt the client in Swift and Kotlin against a shared API contract, moved transaction categorisation on-device, and put release on a phased rollout with automated rollback.

Result

Shipped to both stores in 14 weeks and cleared the compliance review that had blocked the previous build twice.

Cold start, down from 11s
1.2sCold start, down from 11s
App Store, 2,100 ratings
4.8★App Store, 2,100 ratings
Rollbacks since launch
0Rollbacks since launch
Timeline
14 weeks to launch
Team
2 mobile, 1 backend, 1 design, 1 QA
Stack
Swift · SwiftUI · Kotlin · Compose · Core ML · Go · Postgres
Cadence Health — illustrative app screen

Digital health · iOS, watchOS

Cadence Health

Post-surgical recovery tracking that works without a signal

Problem

Patients were expected to log recovery exercises daily, but adherence collapsed after week two and the data arriving was too sparse to be clinically useful.

Approach

Moved capture to the Watch with on-device motion classification, made the entire flow offline-first, and cut daily logging from nine taps to one.

Result

Adherence held past week eight, and clinicians got a continuous signal instead of self-reported gaps.

Week-8 adherence, up from 24%
71%Week-8 adherence, up from 24%
Daily log, down from 9
1 tapDaily log, down from 9
App Store, 840 ratings
4.9★App Store, 840 ratings
Timeline
9 months, ongoing
Team
3 mobile, 1 backend, 1 design
Stack
Swift · SwiftUI · WatchKit · Core Motion · Core ML · HealthKit · Node
Terrafleet — illustrative app screen

Field logistics · Android

Terrafleet

A driver app for crews who spend half their shift out of coverage

Problem

The existing app lost job updates whenever drivers left coverage, and a stalled Play Store submission had blocked releases for seven weeks.

Approach

Introduced a conflict-resolving sync layer with a durable outbox, rewrote the job list against it, and untangled the signing and policy issues holding up submission.

Result

Cleared review on the next submission and eliminated the lost-update class of bug entirely.

Lost job updates since sync rewrite
0Lost job updates since sync rewrite
From engagement to store approval
6 daysFrom engagement to store approval
Google Play, 3,400 ratings
4.6★Google Play, 3,400 ratings
Timeline
6 weeks, rescue engagement
Team
2 mobile, 1 QA
Stack
Kotlin · Compose · Room · WorkManager · Protobuf · Firebase

What we do

Four things, properly.

A studio that lists every capability it has reads as a supplier. We would rather be the specialist you call for the thing that is hard.

01

Discovery & product strategy

A fixed-price sprint that ends with a scope you can actually build, not a deck.

  • User story map and prioritised MVP scope
  • Technical architecture and platform decision
  • Clickable prototype of the core flow
  • Delivery plan with a real date on it

02

Design & build

Native where it matters, cross-platform where it pays. We will tell you which one you need.

  • iOS — Swift, SwiftUI, watchOS
  • Android — Kotlin, Jetpack Compose, Wear OS
  • Cross-platform — React Native, Flutter
  • Backend, APIs and the sync layer underneath

03

On-device intelligence

Features that used to need a backend and a per-token budget now run on the phone in your user's hand.

  • No inference bill that scales with usage
  • No user data leaving the device, so no new DPA to negotiate
  • Works with no signal — the model is already there
  • App Intents, so system assistants can drive your app

04

Release & run

Shipping is a capability, not an event. Most stalled mobile products are stalled here.

  • App Store and Play submission, including the awkward ones
  • Phased rollout with automated rollback
  • Crash, performance and adoption monitoring
  • Post-launch support with a response SLA

Smaller ways in

  • Mobile code audit

    Two weeks. Architecture, performance, crash surface and release pipeline, with a prioritised remediation plan.

  • App Store rescue

    For submissions stuck in review or releases blocked by signing, policy or privacy manifests.

  • Performance remediation

    Cold start, jank and crash rate, measured on real devices rather than a simulator.

How we work

Three shapes of engagement.

Pick the one that matches where you are. We will tell you if you have picked the wrong one.

Embedded team

Our engineers join your standups, your board and your codebase. You keep the roadmap.

You have a product org and need mobile capacity

1–4 engineers · monthly · 4-week notice

Full-cycle delivery

A complete unit — mobile, backend, design, QA and delivery lead. We carry the plan and the risk.

You need the product built and owned end to end

Pod of 4–6 · monthly · 3-month minimum

Fixed-scope sprint

Discovery, an audit, a rescue or a defined feature. Fixed price, fixed deliverables, fixed date.

You need one specific thing finished

2–6 weeks · fixed price

Working together

Overlap is scheduled, not hoped for.

Every engagement has a written overlap window and a named engineer who is awake during it. Nothing important depends on someone reading a thread overnight.

  • Written-first: decisions land in the repo, not in a call
  • A demo build every Friday, whether or not there is a meeting
  • One named point of contact, not a rotating account manager
  • Your own Slack and your own board — we work in your tools

Daily overlap

  • London09:00 – 17:00 GMT8 hours
  • New York09:00 – 12:00 EST3 hours
  • San Francisco08:00 – 09:00 PST1 hour, plus async
  • Berlin · Warsaw09:00 – 18:00 CETFull day

Who actually does the work

Of applicants hired
1.4%Of applicants hired
Average engineer tenure
4.1 yrsAverage engineer tenure
Projects staffed with juniors alone
0Projects staffed with juniors alone

Stack

What we build with.

Chosen per project during discovery, not by habit.
iOS
SwiftSwiftUISwift ConcurrencyCore MLApp IntentsWidgetKit
Android
KotlinJetpack ComposeCoroutinesRoomWorkManagerWear OS
Cross-platform
React NativeFlutterKotlin Multiplatform
Backend
GoNodePostgresgRPCProtobufRedis
Delivery
FastlaneGitHub ActionsPhased rolloutDetoxMaestroSentry

Clients

In their words.

  • “We had been told the compliance problem was a backend problem for eight months. Rubicon moved the categorisation on-device in three weeks and the objection simply stopped existing.”

    Ingrid Molnes

    VP Product, Halden

  • “They pushed back on the scope we came in with, which nobody else had done. The version we shipped was smaller than the one we asked for and it worked.”

    Dr. Amara Okafor

    Clinical Director, Cadence Health

  • “Six weeks from a stuck submission to an approved release. What mattered was that the same two engineers were on it the whole time and I always knew which one to ask.”

    Tomas Berg

    Head of Engineering, Terrafleet

Questions

Including the ones about money.

Publishing a floor saves everyone three calls. If the numbers do not work, better to find out on this page.
  • What does a mobile app actually cost?

    A first release with a real backend usually lands between $90,000 and $220,000 over 12 to 20 weeks. A fixed-scope discovery sprint is $12,000. An embedded engineer starts at $11,000 per month; a full delivery pod runs $34,000 to $52,000 per month. If your number is well under those, we would rather tell you now than after three calls.

  • Do you have a minimum engagement?

    Yes — $25,000. Below that we cannot staff a project without cutting the parts that make it work, and a badly staffed mobile build costs more than not building one.

  • Will I get senior engineers, or a bait-and-switch?

    The people on your calls are the people writing the code. We hire roughly 1.4% of applicants and average 4.1 years of tenure, and we have never staffed a project with juniors alone. Ask for the CVs of the specific engineers before you sign anything, with us or with anyone.

  • How does the timezone work?

    Every engagement has a written overlap window and a named engineer awake during it — typically 8 hours with London, 3 with New York, 1 plus async with San Francisco. There is a demo build every Friday whether or not there is a meeting.

  • Who owns the code?

    You do, from the first commit. Work is delivered into your repositories and your store accounts. There is no license to renegotiate later and nothing that stops you leaving.

  • Native or cross-platform?

    It depends on what your app does, and we will give you a straight answer during discovery rather than defaulting to whatever we would rather build. Heavy device integration, tight performance budgets and platform-specific UI favour native. Content-led products with small teams often do better cross-platform.

  • Can you take over an existing codebase?

    Often, and it is a large share of what we do. It starts with a two-week audit covering architecture, performance, crash surface and the release pipeline, ending in a prioritised plan. Sometimes that plan says rewrite, and sometimes it says the code is fine and the problem is the release process.

  • Will you sign an NDA?

    Yes, and you can read ours before you write to us — it is linked in the contact section below. If your legal team prefers your paper, we will sign that instead.

  • What happens after launch?

    Support with a response SLA, crash and performance monitoring, and OS-version upgrades. Launch is when a mobile product starts costing money, not when it stops.

Start here

Tell us what you're building.

One email, three things worth including. You will get a reply from an engineer, not a sales inbox.
  1. 01What you're buildingA new product, an existing app to take over, extra mobile capacity, or an audit.
  2. 02Timeline and budget bandA range is fine. It is the fastest way to find out whether we are a fit.
  3. 03How to reach youName, company, and whether you would rather write or talk.

Write to us and we will reply with questions, not a brochure.

Estimate project

We reply within one business day, with a named engineer on the call.

Read our standard NDA before you write to us

Or write directly to hello@rubiconcreators.com