Services / Mobile App Development
Mobile apps that ship, and keep shipping
We design and build iOS and Android apps from one codebase, publish them to both stores and keep improving them after launch. You pay for one product and get a partner who looks after it at every stage.
Free consultation. We'll tell you if you need an app at all – sometimes a mobile-first web app is the cheaper answer.
Overview
Where mobile apps usually get stuck
Two separate teams for iOS and Android – two budgets, two different products
The build finished months ago and it's still not in the stores
Apple rejected it and nobody on the project knows why
People install it once and never come back
It crashes on the newest OS version and the original developers are gone
Every small change means a new release and another round of store review
Field staff lose connection and the app becomes useless
You have installs but no idea where users drop off
Almost none of this is about code quality. It's about who owns the release, the store accounts and the first month after launch.
Not every app has the same job
A consumer product is built differently from a tool your warehouse team uses. Tell us the goal and we'll define the scope, including what you can safely cut.
MVP for a new product
The smallest version that proves the idea, in the stores fast, ready to grow or to pivot.
Customer app for an existing business
Loyalty, bookings, orders, account access. Connected to the systems you already run.
Internal app for your team
Field service, inventory, inspections or delivery. A tool that speeds up your team's daily work, even without signal.
App for your hardware
An app that connects to your devices, sensors or machines and lets people manage them comfortably from a phone.
Rescue or modernisation
You have an app that's slow, unmaintained or abandoned. We take over the codebase and stabilise it.
Mobile companion to your web system
Your platform in your users' pockets, working on the same data as the web version.
Not sure it needs to be an app? If a mobile web app does the job for less, we'll recommend that instead.
What you can count on
- 1 codebase
- Two platforms, one release, one budget
- Release
- We handle publishing to the App Store and Google Play
- Day 1
- The store accounts are in your name
- SLA
- Response times written into the contract
The parts that decide whether it works
These are the pieces that separate an app people keep on their home screen from one they delete after a week.
One codebase, both platforms
iOS and Android built together – same features, same release, one team, one budget.
- One React Native codebase
- Consistent behaviour on both platforms
- Quick fixes without waiting for the stores
- Swift or Kotlin where it's needed
One codebase
Both stores, one release
Dashboard
Active users
2,842
↑ 18.2%Dashboard
Active users
2,842
↑ 18.2%Intuitive on every screen
Interfaces drawn to the pixel and tuned for how a phone actually gets used – one hand, on the move, in daylight.
- Interface designed for your product
- Gestures and motion that feel native
- Accessibility as standard
- Layouts that fit every screen
Order #2043
Awaiting collection
12 items
Bay 4 · Aisle 2
Ready since 13:52
One hand, one thumb
Easy
Primary actions – Confirm pickup, Scan barcode
Stretch
Secondary taps, never the main flow
Out of reach
Cancel order, on purpose – a mis-tap is expensive
Works without signal
Your users won't always have a connection. The app shouldn't care.
- Data stored safely on the phone
- Automatic data sync
- Safe for several people at once
- No lost work
Sync engine
No connection. Every action is written to the phone's own database first.
Outbox
4 queued- Photos · 618:14queued
- Time on site18:18queued
- Parts used18:21queued
- Signature18:23queued
Notifications people don't mute
Push done properly brings users back. Push done badly gets your app deleted.
- Notifications tailored to each user
- Links straight to the right screen
- Settings users control themselves
- Campaigns and in-app messages
Tuesday, 4 March
9:41
Push → deep link
- Segment
- Streak of 7 days or more
- Trigger
- no_session_by_20:00
- Deep link
- move://workouts/quick
Tap a notification to follow it
Delivery report
Everything the device can do
Camera, sensors, wallet, hardware – the reasons an app beats a website.
- Camera and document scanning
- Fingerprint and face login
- Maps and location
- Bluetooth device connections
Scan document
Edges found – hold steady
FV-2043 · 1 240 PLN
On-device, natively
- API
- expo-camera · VisionKit
- Prompt
- Camera – asked once, on the first scan
Real platform APIs and permission prompts – not a website in a wrapper.
Accounts, payments and subscriptions
Accounts and payments set up to meet both stores' rules.
- Sign-up and easy login
- Roles, permissions and secure login
- In-app purchases and subscriptions
- Renewals and refunds handled
Upgrade
Unlimited reports
Auto-renews yearly. Cancel anytime.
Subscription lifecycle
Free plan. The sheet carries the price, the term and a restore link – the first three things review checks.
- In trial7 days, then it charges
- ActiveRenews until someone stops it
- CancelledAccess to the end of the period
- RefundedStore webhook revokes access
- Price and renewal term on the sheet
- Restore and cancellation inside the app
- Receipts, renewals and refunds handled
Connected to your systems
The app is a front end. We build or connect what sits behind it.
- A new backend or your existing system
- ERP, CRM and other business systems
- Admin panel for your team
- Shared data with your web app
Store release, handled
We plan the store release from the start, as part of the build.
- Store accounts in your company's name
- A store listing that sells the app
- Compliance with store requirements
- Smooth release of every update
App Store Connect
- Version
- 2.8.0
- Build
- 412
- Review
- 1 day
Submission checklist
- Privacy manifestRequired APIs declared
- Data declarationsBoth store forms
- Review notesDemo account included
- Screenshots & ASOEvery required size
- TestFlight buildBeta group signed off
The accounts are in your name from day one – so the listing, the reviews and the users stay yours.
Analytics and crash reporting
After launch you'll know what users do, not just how many downloaded.
- User behaviour and engagement
- Early crash detection
- App performance monitoring
- Regular, easy-to-read reports
Retention
48%Day 7Crash-free
99.7%
of sessions, last 30 days
Crashes by device & OS build
7 days- NSInvalidArgumentiPhone 13 · iOS 18.314
- OutOfMemoryErrorGalaxy A14 · Android 149
- TimeoutExceptionPixel 7 · Android 153
AI inside the app
Features that once needed a research team, running on your users' phones.
- An assistant that knows your product
- Image and document recognition
- Voice data entry
- Personalised feed and recommendations
What the model ends in
Point the camera at a shelf. The part is recognised on the device and added to the order.
- CaptureOn-device camera
- RecogniseVision model
- ActLine added to the order
Something else in mind? Describe it and we'll tell you what it takes to run on a phone.
Talk to usBuilt on a mainstream stack any team can take over
We build for iOS and Android on proven, widely used technology, from the app itself to the cloud it runs on. No proprietary frameworks, so any experienced team can take your app over.
Apps in the stores, in use
Three projects with different goals. We show what clients have agreed to share.
Driver app with offline routes
The problem: drivers lost the app the moment they left coverage, so deliveries were reconciled on paper after every shift. What we built: one iOS and Android app that works offline and syncs routes and deliveries once the signal returns.
Inspection app with photo capture
The problem: inspections were recorded on forms and retyped into the office system days later. What we built: an inspection app that works offline, captures photos and signatures, and sends results straight to the client's office system.
Consumer app with subscriptions
The problem: a previous submission had been rejected repeatedly and the subscription flow never passed review. What we built: a consumer app with in-app subscriptions configured in both stores, approved on the first attempt.
Your business in your customers' pockets. One iOS and Android app that your customers and your team use every day, wherever they are.
What clients say after launch
We'd been quoted twice as much for two separate teams. One codebase, both platforms, and honestly you can't tell it isn't native.
Logistics
Driver app with offline mode and route sync
Our previous agency got rejected three times and blamed Apple. These guys got it approved first try and explained exactly why the earlier submissions failed.
Fintech
Consumer app with in-app subscriptions
The app works in a basement with no signal, which was the entire point and the thing the last developer said was impossible.
Field services
Inspection app with offline sync and photo capture
From idea to both stores
You always know what's built, what's next and when it goes live.
01
Free consultation
We get to know your goal and your users, and you leave with a recommended scope and a rough estimate, no strings attached.
02
Scope & MVP definition
We pick the features that test the idea fastest and make the best use of your budget.
03
Design & build in sprints
We design and build in short iterations, and you try the app on your own phone from the start.
04
Testing & store submission
We test the app on a wide range of devices and prepare everything the stores require.
05
Launch, handover & care
You receive the code, accounts and documentation, and we keep the app stable and growing after launch.
We build store review into the timeline from the start.
Three ways to run the project
Pick the model that fits your product's stage. Not sure? We'll tell you which one we'd choose.
Fixed price
Best for
- MVPs and apps with a clear scope
We agree the scope and price before we start, with the stages set out in the contract.
Get a fixed quoteTime & materials
Best for
- Products that grow in stages
You pay for the time worked and adjust priorities as your users' needs change.
Ask for detailsCare & growth
Best for
- Apps already in the stores
We take care of updates, store requirements and new features for a fixed monthly fee.
See care plansNot sure which model fits, or whether you need an app at all? Book a call and get technical advice you can use even if you go elsewhere.
doubleucode · Free consultation · Call: +48 667 083 196
Frequently asked questions
Can't find your question? Email us:
Ask a questionWhy cross-platform instead of two native apps?
For most business apps, one codebase gives the same result on a smaller budget, and you get one consistent product instead of two. Separate native apps make sense for very demanding graphics or features tied closely to one platform. If your project is one of those, we'll tell you.
Will users notice it isn't native?
Not if it's built well. People complain about badly built apps, not cross-platform ones. We focus on smooth performance and test on real phones.
How much does a mobile app cost?
Cost depends mainly on scope: the features and the systems the app connects to. A simple MVP and a full product with payments are very different projects. We'll go through the details in a free consultation.
How long until it's in the stores?
It depends on the scope. We give you a timeline once we've agreed what goes into the first version, and larger products ship in phases so something real goes live early.
What do I need before we start?
A clear goal and a decision-maker on your side. We'll handle the rest together, store accounts included.
Do I have to give Apple and Google a percentage?
In some cases, yes. Apple and Google take a commission mainly on digital goods such as subscriptions. Before you decide how the app makes money, we'll check which rules apply to you.
Can you take over an app someone else built?
Yes. We first review the code and setup, then tell you honestly whether the app needs fixing or a rebuild. Sometimes a new version costs less than repairing the old one.
What happens when Apple or Google release a new OS version?
Apple and Google change their requirements every year, and apps that aren't updated eventually stop working. A care plan covers this: we prepare your app for new system versions ahead of time, so your users don't feel the change.
Who owns the code and the store accounts?
You do, in full. The code, designs and store accounts are yours, whether or not you keep working with us.
Will you help get downloads?
Yes. We make sure the app presents well in the stores and that analytics show where your loyal users come from. Paid campaigns are outside our scope, but we're happy to work with whoever runs them for you.
Can the app work without internet?
Yes, and for field teams it usually should. The app saves data on the phone and syncs it on its own when the signal returns, so nothing gets lost.
Do you also build the backend and admin panel?
Yes. We build the backend from scratch or connect the app to the systems you already use, and we usually add a panel for managing content and users. Get in touch and we'll find the right setup for your company.