Custom Mobile App Development
A Mobile App Development Company That Picks The Stack First
Most app projects are settled before anyone writes a line of code, in the meeting where somebody chooses iOS, Android or a shared codebase for a reason nobody can repeat six months later. We start at that decision, make it against your roadmap, and then build.
Triple Protection Guarantee
- US-Registered Entity
- Signed IP Assignment
- Senior Engineers Only
Triple Protection Guarantee:
- US-Registered Entity
- Signed IP Assignment
- Senior Engineers Only
Years In Business
0
+
Engineers On Staff
0
+
Avg. Engineer Exp.
0
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Where Apps Go Wrong
Stack Decision
On Evidence
Senior Engineers
Vetted Only
Timezone Overlap
Live Hours
Store Release
Planned First
Delaware LLC
US Entity
Device Matrix
Real Devices
Reviewed Merges
Code Review
Analytics From Day One
Measurable
Offline Rules
Documented
IP Assignment
Signed
Delivery Overlap
Fixed
Hours
App & Accounts
You
Trusted By Startups
What Mobile App Development Actually Involves
Mobile app development is the work of turning a product idea into something that installs on a phone, survives an app store review and keeps working on a four-year-old handset with no signal. That covers far more than screens. It covers the API the app talks to, what happens when the network drops mid-action, how consent and push permissions are asked for, and how a fix reaches users once the app is already installed on thousands of devices.
Stallyons is registered in Delaware as a US company, and our engineers work a time-zone window agreed before the project starts, with four-plus hours of daily overlap. You sign a US contract, run diligence on a US entity and pay one US invoice. Behind the work sits twelve-plus years of delivery across six continents and around thirty-five engineers, averaging four-plus years of production experience. Founders, product owners and CTOs come to us for custom mobile app development that has to last past its launch week.
What A Mobile Build Covers
A stack chosen on evidence: native, shared codebase or web-wrapped, argued against your roadmap, budget and team rather than picked because it is what the last vendor happened to be good at.
A backend designed for a phone: pagination, token refresh, versioned endpoints and payloads sized for a mobile connection, instead of a web API that the app has to work around on every screen.
Offline behaviour specified before the build: what stays readable with no signal, what queues, what refuses, and which side wins when the same record was edited in two places.
Store submission treated as a milestone: privacy labels, permission strings, account deletion and review notes prepared in advance, because rejection costs a week you did not plan.
Releases you can undo: phased rollout, crash and adoption dashboards watched during the ramp, and a rollback that has been rehearsed rather than improvised at midnight.
One accountable vendor: one contract, one invoice and one entity for legal and finance to run diligence on, instead of a design shop, an app team and a backend contractor blaming each other.
What To Ask Any Mobile App Development Company First
- Ask why they would choose that stack for you. If the answer arrives before they have asked what the app does, you are being sold their bench rather than a decision.
- Ask who submits to the stores and whose developer accounts are used. Your own Apple and Google accounts, or you are renting your own product back from a vendor.
- Ask what the app does with no connection. A team that has not thought about offline has not thought about the two screens users hit most on a train.
- Ask how a fix reaches users. Store review takes days, so the release plan, the phased rollout and the rollback path matter more than how fast a feature gets built.
- Check the exit before you need it. Repositories, store listings, signing keys and cloud accounts sit in your own name from day one, so leaving is administration.
- Ask which devices get tested on. Simulators hide thermal throttling, older chipsets and the mid-range Android handsets most of your users are actually holding.
How A Mobile App Project Starts Here
Every project starts with a free 45-minute scoping session. No slide deck, no sales script. You bring the product, the users and the constraints; you leave with a stack recommendation, a scope and a timeline.
We are selective about new projects and cap how many we run at once, because the scoping is the product. If your idea would be better served by a website than an app, we will say so before you buy one.
Why Clients Choose Us
Full
Written IP Transfer
USA
Contract Entity
Yours
Stores & Signing
Named
Delivery Lead
Ready to build an app that survives its launch week?
What We Build In Mobile
The Mobile App Development Work We Deliver
Every app is a different product, and the underlying jobs repeat: choose the stack, build the client, feed it a proper API, prove it on real devices and get it through review. These are the builds we deliver most often.
Native iOS Development
Swift, SwiftUI, App Store releases
Store-Ready
Native Android
Kotlin, Compose, Play releases
Play Store Set
Shared Codebase
React Native, Flutter, Ionic builds
Two Apps
App Modernisation Work
Rewrites, upgrades, migrations
Live In Production
Mobile APIs
Auth, sync, push, versioning
Documented
Payments & Billing
IAP, subscriptions, receipts
Collected
Offline Data & Sync
Local store, queues, conflicts
Usable
Device & QA Testing
Real devices, regression, release sign-off
Sign-Off
Store Release Runs
Review, phased rollout, rollback
Shipped Clean
Support & Maintenance
OS updates, fixes, releases, cover
Kept Current
Not sure which platform to build on? Let us map it out.
Common Challenges
Why Do Mobile App Builds Fail?
Six patterns behind almost every app that has to be rebuilt within two years. All six start as a reasonable shortcut.
Stack By Default
01
The framework is chosen because it is what the vendor already staffs, not because it suits the product. Every constraint that decision creates is then paid for on every screen for the next three years.
Web API, Phone App
02
The app is handed an API built for a browser. Screens fire six calls each, payloads arrive megabytes deep, and the phone burns battery reassembling a web page.
Offline Never Defined
03
Nobody decides what happens with no signal, so the app shows a spinner forever on a train. The fix arrives later as a retrofit across every screen at once.
Store Review Shock
04
Submission is treated as a formality until it is rejected over a permission string, a missing account-deletion path or a privacy label nobody filled in, and launch slips a fortnight.
Tested On Simulators Only
05
Everything is smooth on a new handset on office wifi. The mid-range Android device most of your users hold overheats, drops frames and runs the battery flat by lunchtime.
Nobody Owns The Release
06
Builds are made by hand on somebody's laptop, so nobody can say which commit is live, and a bad release cannot be rolled back without another store review.
Recognise a few of these? Let us do it properly.
Our Mobile App Work
Our 6 Mobile App Development Services
Six ways to buy mobile delivery from one accountable vendor. Run one, or run several in parallel under a single contract.
Custom Mobile App Development
01
A product built end to end: stack decision, API design, app, store submission and launch, with a named lead who reports into you and a written plan you approve before work starts.
Enterprise Mobile App
02
Internal and field apps that meet your security review: single sign-on, device policy, audit trails, and distribution through your own managed channel rather than a public listing.
App Rewrites & Upgrades
03
Ageing apps modernised in stages, with the current version still shipping to users until the replacement has earned the switch on crash rate and adoption.
Mobile Backend & APIs
04
The service layer behind the app, designed for phones and built by our own API development practice: auth, sync, push and versioning.
Device QA & Test Runs
05
Testing on a real device matrix rather than simulators: manual passes, automated suites, regression before every submission and a written release sign-off.
Release & Support Retainers
06
Store releases, OS-version updates, crash triage and dependency maintenance on a standing cadence, so the app does not quietly rot between funded projects.
Not sure which piece you need first? Let us scope it together.
Why Choose Us
What Makes Our Mobile App Development Different
The details that decide whether an app is still healthy in its third year, not its first month.
A US Legal Entity
01
Stallyons is registered in Delaware. Your contract, your invoice and your legal recourse sit with a US company, not an unknown one.
The Stack Is Argued
02
We write down why a platform suits your product, including the cases where it does not, so the choice can be challenged before it is expensive.
Overlap You Set
03
You choose the hours we share with your working day, and stand-ups, reviews and escalations all happen inside that window.
Real Device Testing
04
Every release is exercised on a matrix of real handsets across OS versions and price tiers, because a simulator will never show you thermal throttling.
Reviewed Code
05
Every merge is reviewed against an agreed definition of done, on your board, where you can read it yourself.
One Contract
06
One contract covers the engagement, so procurement, legal and finance each deal with a single named counterparty.
Ready to see what a proper mobile build looks like?
Our Process
From First Call To App Store Launch In Six Steps
A build process that settles the platform, the API and the release plan before any screens.
Discovery
Understand the users, devices and systems in play
Scoping
Agree the platform, scope and cost model
Design
Flows, screens, API contract and offline rules
Contracting
NDA, IP assignment, access and onboarding
Release
Store submission, then phased rollout
Tune & Scale
Read crash and adoption, then widen release
Want to see how this maps to your roadmap?
Technology Stack
What Our Mobile App Developers Work With
The platforms we build on and the engineering around them: backends, app services, testing, release.
Native Builds
Swift / SwiftUI
Kotlin Android
Objective-C, Java
Xcode Build
Store Setup
Shared Codebase Options
React Native
Ionic / Capacitor
.NET MAUI 9
Flutter
PWA / HarmonyOS
Backend & APIs
Node.js / NestJS
Python Django
PostgreSQL / Redis
MongoDB Atlas
REST & GraphQL APIs
Mobile Services
Firebase Suite
Push & Links
In-App Buys
Maps & Locations
Analytics & Crash
Ship & Operate
AWS / GCP Hosting
GitHub Runs
Fastlane Lanes
Appium / Selenium
Datadog Monitoring
Who We Build This For
Mobile App Development For Regulated And High-Volume Sectors
Eight kinds of product with different users and one shared need: an app that behaves on a bad connection.
Fintech & Payments
Onboarding, KYC, card controls
Healthcare & HealthTech
Patient apps, records, reminders
Retail & Commerce
Catalogue, checkout, loyalty
EdTech & Learning
Lessons, offline content, tests
SaaS & Digital Products
Companion apps, billing, sign-up
Logistics & Field Teams
Routes, scanning, proof of job
Travel & Hospitality
Booking, boarding, itineraries
Real Estate & PropTech
Listings, viewings, tenancies
Working in another sector? See all industries we serve.
How We Compare
Your Mobile App Delivery Options, Compared
An honest look at your four delivery options.
| Capability | Native-Only Studio | Freelance App Team | No-Code App Builder | Stallyons Technologies |
|---|---|---|---|---|
| Choosing the stack | Always native | Whatever they know | ✕ Locked to platform | Argued against your roadmap |
| Backend and API design | Often out of scope | ✕ Sub-contracted | Templated | Built with the app |
| Offline behaviour | Case by case | ✕ Rarely modelled | ✕ Online only | Specified before build |
| Store submission & review | Handled well | Sometimes | Their account | Rehearsed, your accounts |
| Release automation | Manual builds | Manual builds | Push-button | CI with phased rollout |
| Device and OS coverage | Deep on one platform | Simulators mostly | Vendor's list | Real device matrix |
| Contracting entity & ownership | Varies | ✕ Marketplace terms | ✕ Platform lock-in | US-registered LLC, your accounts |
See the difference for yourself
Complete Engagement
Everything Included In Your Mobile App Development Project
From Scoping to Contracting to Delivery, One Vendor
Here is everything included when you build your app with us:
One Mobile App Build Price: No Hidden Fees, No Surprises.
Every mobile engagement includes all eight components above. One contract, one senior team, one predictable cost, and no vendor sprawl.
🔒 No obligation. We'll deliver a detailed proposal within 48 hours.
Plus, Get These Free Bonuses
Free Mobile App Review
A written read on your stack options, API readiness, offline gaps and store risk, with the fixes ordered by what breaks first. Yours to keep.
Included Free
Build Plan And Estimate
A phased build plan with scope, milestones, the platform recommendation and a transparent, itemised estimate for the engagement.
Included Free
Free Vendor Checklist
The questions we would ask any mobile app development company about stacks, stores, offline and releases, so you can test us too.
Included Free
Risk-Free Partnership
Our Mobile Development Promise
We stand behind every engagement with commitments that protect your investment.
01
Scope Agreed First
Scope, model, working hours and cost structure are written down and agreed before contracting, so nothing is discovered later.
02
Built to Last
Senior developers, code review, automated tests, security and accessibility audits, and clean, documented code you fully own.
03
IP And Access Protected
NDA and IP assignment are signed before access, permissions are scoped per person, and your accounts stay under your control.
Start your mobile app build with confidence, backed by our Triple Protection Guarantee.
Track Record
Engagements That Ship, Scale, and Compound
500+
Projects Delivered
29+
Service Categories
81%
Repeat Client Rate
4.9 ★
Clutch Rating
"Stallyons took our Figma design and built it into a live web application, a cognitive game with level-based match play, messaging, a tutorial, and a directory that ranks users nationally. What impressed me most was their grasp of the code behind that logic, and the quality of the experience. Delivered on time with steady updates."
Jerry L.
Founder
PicCiti LLC
"We brought Stallyons in to absorb an overflow of work, and they delivered ten iOS and Android apps, from reporting to geo-location for logistics, plus several backend systems, owning design, development, and app-store submission. Everything stood out: code quality, speed, and reliability. Perfect code, on time, adopted company-wide."
William B.
Director
Amplo Solutions
FAQ
Frequently Asked Mobile App Development Questions
Mobile app development covers everything between an idea and an installed app: the platform decision, the interface, the API the app talks to, offline and sync behaviour, payments, push, analytics, store submission and the release process afterwards. Mobile app development services that stop at the screens leave you owning the difficult half, which is the part that decides whether the app survives its second year.
It depends on how much of your product is interface and how much is platform. Native wins where you lean on new OS features, heavy background work or tight hardware access. A shared codebase wins where the same screens have to exist twice and your team already writes JavaScript or wants one design system everywhere. We argue it per product, and our cross-platform page sets out the trade-offs.
Cost follows the number of screens, how much of the backend already exists, whether the app must work offline, and how many platforms it ships to, so a figure before scoping is guesswork. Integrations and offline sync move it most. We scope first, then price, and itemise what each phase covers so you can cut before you commit rather than after.
Ask why they recommend a stack before hearing what the app does, and be wary if an answer arrives quickly. Ask whose Apple and Google accounts the app ships under, which real devices get tested, and how a bad release is rolled back. The best mobile app development company for you is the one whose answers describe your product rather than their bench.
You do, from the first day. The repositories, signing keys, Apple and Google developer accounts, cloud accounts and analytics all sit in your name, and NDA and IP assignment are signed before anyone gets access. Everything produced on the engagement is assigned to you outright, with no licence-back.
Usually. We start with a read of the code, the dependency versions, the crash data and the release process, then give you an honest answer on repair versus rewrite with the reasoning written down. Where the app is worth keeping we stabilise it first, ship a release under our own process, and only then start changing behaviour.
As a milestone with its own preparation, not a formality at the end. Privacy labels, data-safety forms, permission strings, account deletion and reviewer notes are prepared while the app is built, and we submit under your own developer accounts. Releases then go out in phases so a problem reaches a small group first.
If the job is reach and content, and users arrive from search or a link, a browser-based build is usually cheaper and faster to change. An app earns its place when you need reliable offline use, background work, hardware access or a home-screen habit. The trade-offs sit on our progressive web app page.
Still have questions? Let's talk.
Schedule an appointment with us today!
Ready To Build A Mobile App That Lasts Years?
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