Expert Cross-Platform App Development Company UK | React Native & Flutter Specialists
Launch high-performance iOS and Android apps from a single codebase—cut costs by 60–70%, go live 50% faster, and maintain one unified product. We architect with React Native, Flutter, and Xamarin, and we’re framework-agnostic—your requirements choose the tech, not hype.
Project budgets from £25K to £300K+. Based in the UK, delivering globally.
Looking for our broader services? Explore our Mobile App Development Company capabilities.
› Open Table of Contents
What you'll find on this page
- Why Choose Cross-Platform
- Our Technologies (React Native, Flutter, Xamarin, Ionic, PWAs)
- Cross-Platform vs Native
- Our Development Process
- Types of Apps We Build
- Cost & ROI Analysis
- Security & Performance
- Portfolio & Success Stories
- React Native vs Flutter vs Xamarin
- App Store Optimisation
- 18 Cross-Platform FAQs
- Ready to Build?
Cross-Platform at a Glance: Visual Benchmarks & ROI Infographics
Why Choose Cross-Platform App Development?
Cost Efficiency: One Codebase, Multiple Platforms
Cross-Platform App Development lets you build once and ship everywhere. Instead of two native teams, we run a single cross-functional team, reusing 60–80% of code while still enabling platform-specific finesse where it matters.
- 60–70% savings vs dual native builds
- Shared design system and components
- Unified QA and test automation
Faster Time-to-Market
Launch iOS and Android simultaneously. Our pipelines push updates to both app stores in sync, meaning you capture market share earlier and iterate based on unified analytics, not two separate codebases.
- 50% faster initial release
- Over-the-air updates (where applicable)
- CI/CD built for parallel delivery
Consistent User Experience Across Devices
We respect platform conventions while maintaining your brand’s visual system. The result: a clean, consistent experience that feels native on iOS and Android.
- Platform-aware navigation
- Adaptive theming (Material + Cupertino)
- Shared motion & micro-interactions
Easier Maintenance and Updates
With a single codebase, bug fixes and feature releases land across iOS and Android at the same time. No divergent roadmaps. No duplicated effort.
- One backlog, one roadmap
- Fewer regressions and edge case drift
- Simplified security patching
Our Cross-Platform Development Technologies
React Native Development Excellence
We deliver React Native apps with near-native performance and native modules where needed. Tooling includes:
- React Native 0.72+, TypeScript, Expo SDK & Router
- State: Redux Toolkit, Zustand, React Query
- UI: React Native Paper, NativeBase, Reanimated 3, Lottie
- Perf: Metro tuning, Hermes, Flipper debugging
- OTA: CodePush for rapid updates
- Features: RN Firebase, Maps, In‑App Purchases
Best for: enterprise apps, social platforms, marketplace products, content-driven experiences.
Flutter Development Mastery
We build Flutter apps with pixel-perfect UI and smooth animations across iOS, Android, Web, and desktop.
- Flutter 3.16+ with Dart 3; Material & Cupertino widgets
- State: Provider, Riverpod, Bloc; GetX when appropriate
- Networking & Data: Dio, Hive, SQLite, Firebase
- Platform Channels for native capabilities
- Tooling: Flutter DevTools, Flavors, Codemagic CI/CD
- Web/Desktop readiness
Best for: UI-heavy products, data visualisation, multi-platform expansion (Web/Desktop).
Xamarin & .NET MAUI Solutions
When your organisation is invested in .NET, Xamarin and .NET MAUI can be a pragmatic path.
- Shared C# codebase, MVVM patterns
- Seamless integration with Microsoft stack
- Enterprise SSO, Azure AD, Intune compliance
Best for: established Microsoft environments and enterprise security requirements.
Ionic Hybrid Development
Ionic + Capacitor delivers fast builds for simpler apps and robust PWAs with native plugins when needed.
- Leverages web skills (Angular/React/Vue)
- Rapid MVPs, content apps, internal tools
- Capacitor for device features
Progressive Web Apps (PWAs)
Installable, offline-first experiences with near-native feel—no store friction, instant updates.
- Service Workers, caching strategies
- Push notifications, background sync
- SEO-friendly and shareable
Cross-Platform vs Native: Complete Comparison Guide
| Dimension | Cross-Platform App Development | Dual Native (iOS + Android) |
|---|---|---|
| Time-to-Market | Faster. Ship iOS + Android together; one backlog and CI/CD. | Slower. Two codebases and staggered releases. |
| Cost | 60–70% savings thanks to code reuse and unified team. | Highest—duplicate engineering, QA, and PM effort. |
| Performance | Near-native when architected correctly; native modules for critical paths. | Excellent—full access to platform internals by default. |
| Feature Access | Extensive via framework APIs + native bridges/platform channels. | Complete. New features available instantly as Apple/Google ship them. |
| Maintenance | Simpler. One codebase, unified updates and bug fixes. | Complex—divergence risk and doubled maintenance workload. |
Performance Analysis
Modern React Native (Hermes, Fabric) and Flutter (Impeller/Skia) close the gap with native. For animation-heavy, graphics-intensive scenarios, we selectively implement native modules to ensure buttery performance.
Development Cost Comparison
Cross-Platform typically reduces build costs by 40–70% and maintenance costs by 30–50% across three years. See ROI below for a realistic model.
Feature Accessibility
Most device capabilities—camera, GPS, biometrics, push notifications, NFC, Bluetooth—are available via mature libraries. If bleeding-edge platform features are required, we bridge or go native for that module only.
When to Choose Each Approach
- Choose Cross-Platform if you need iOS + Android fast, within one team, and want long-term maintenance simplicity.
- Choose Native if you require ultra-low-level platform access or OS-specific innovation at the bleeding edge.
Our Cross-Platform Development Process
Platform Strategy & Architecture Planning
- Requirements & platform fit analysis
- Framework selection matrix (React Native / Flutter / Xamarin / Ionic)
- Architecture blueprint: state, navigation, modularity
- Security model (auth, data, encryption)
Duration: 1–2 weeks
UI/UX Design for Multiple Platforms
- Design system built for Material + Cupertino
- Adaptive components & responsive layout
- Interactive prototypes user-tested across devices
Duration: 2–3 weeks
Cross-Platform Development & Testing
- Core feature development and API integration
- Platform channels/native modules where needed
- Automated testing and device labs
Duration: 8–20 weeks
Simultaneous Deployment & Launch
- Submission assets for App Store & Google Play
- Compliance checks and privacy policies
- Launch coordination & post-launch monitoring
Duration: 1–2 weeks
Not sure whether React Native or Flutter is right for you? We’ll run a one-hour technology selection workshop with your stakeholders and provide a recommendation with trade-offs, costs, and a delivery roadmap.
Types of Cross-Platform Apps We Build
Enterprise Cross-Platform Solutions
Secure, scalable apps with SSO, MDM/Intune, role-based access, offline-first workflows, and robust analytics.
E-commerce Multi-Platform Apps
Seamless shopping, native payments, wishlists, real-time inventory, and personalised promotions via analytics.
Social & Communication Platforms
Real-time chat, feeds, media sharing, push notifications, deep links, and growth loops baked in.
Fintech & Banking Applications
Biometrics, device binding, encryption, PSD2/SCA compliance, audit trails, and SOC2-ready infrastructure.
Healthcare & Wellness Apps
HIPAA/GDPR-aware data flows, appointments, remote monitoring, wearables integration, coaching dashboards.
Cross-Platform App Development Cost & ROI Analysis
Investment ranges (UK market)
- Simple Cross-Platform App: £25,000–£50,000
- Medium Complexity: £50,000–£120,000
- Enterprise Solution: £120,000–£300,000+
You get a single, unified codebase, simultaneous iOS/Android, and a leaner maintenance profile—unlocking faster ROI.
Development Cost Comparison (Medium Complexity App)
| Approach | Development Cost | Timeline | Maintenance Cost/Year | Total 3-Year Cost |
|---|---|---|---|---|
| Dual Native (iOS + Android) | £150,000 | 32 weeks | £30,000 | £240,000 |
| Cross-Platform | £85,000 | 18 weeks | £18,000 | £139,000 |
| Savings | £65,000 (43%) | 14 weeks faster | £12,000 (40%) | £101,000 (42%) |
Why Cross-Platform Delivers Superior ROI
- Single Development Team: no duplicate roles
- Unified Timeline: parallel delivery, fewer dependencies
- Shared Resources: 60–80% code reuse
- Simplified Maintenance: one codebase, one test suite
- Faster Market Entry: earlier acquisition and revenue
- Scalability: add Web/Desktop later with minimal rework
Cross-Platform Security & Performance Optimization
Security Standards We Implement
- Biometric auth, device binding, secure keychain/keystore
- Encrypted storage (MMKV/Hive/SQLCipher)
- SSL pinning, certificate transparency
- OWASP MASVS-aligned reviews
- GDPR-first data design, DPA guidance
Performance We Engineer
- Startup optimisation: bundle splitting, lazy loading
- 60fps UI: Reanimated/Impeller + GPU-friendly patterns
- Network efficiency: caching, retries, backoff
- Memory/CPU profiling, battery impact minimisation
We align security and performance budgets to your risk profile—finance and healthcare receive deep hardening and audit support.
Our Cross-Platform App Portfolio & Success Stories
FinPay (Fintech)
React Native app with biometric login, instant payments, and 3D Secure. We bridged native modules for encryption and achieved near-native performance.
Impact: simultaneous App Store + Google Play launch; accelerated roadmap with OTA updates.
HealthCoach+ (Healthcare)
Flutter-based wellness platform with wearables integration, offline care plans, and secure messaging.
Impact: unified analytics across platforms improved retention by focusing on high‑value features.
ShopWave (Retail)
Cross-platform commerce with native payments, real-time inventory, and personalised promotions.
Impact: single team, 60% lower upkeep vs dual native; consistent brand experience across devices.
Want to see code architecture and metrics? Request a redacted case study pack.
React Native vs Flutter vs Xamarin: Technology Comparison
Cross-Platform Framework Comparison: Expert Analysis
| Framework | Performance | Development Speed | Community Support | Best For | Garage2Global Rating |
|---|---|---|---|---|---|
| React Native | 95% of native | Very Fast | Largest community | Enterprise, Social apps | 9.5/10 |
| Flutter | 98% of native | Fast | Growing rapidly | UI-heavy, Gaming | 9.3/10 |
| Xamarin | 90% of native | Moderate | Microsoft ecosystem | Enterprise, .NET shops | 8.5/10 |
| Ionic | 80% of native | Very Fast | Web developers | Simple apps, PWAs | 7.8/10 |
Framework Selector
Answer a few questions to get a personalised recommendation.
What matters most?
Your recommended framework will appear here.
Cross-Platform App Store Optimization Strategy
Store Readiness
- Keyword research for both stores
- Conversion-optimised icons, screenshots, videos
- Privacy labels & permissions rationale
Post-Launch Growth
- A/B tests of store assets (creative sets)
- Ratings/reviews playbook
- Deep links & deferred deep linking
We coordinate simultaneous App Store + Google Play submissions and streamline approvals for faster go‑live.
Cross-Platform Savings Calculator
Estimate savings vs dual native development:
Feature Compatibility Checker
Check availability across frameworks:
Result: Fully supported via mature libraries in React Native and Flutter; native modules available for edge cases.
Cross-Platform Development Timeline
Get an indicative timeline for your cross-platform project:
Your timeline estimate will appear here.
Cross-Platform App Development FAQs
What is cross-platform app development and how does it work?
›
Cross-platform app development allows you to build mobile applications that run on both iOS and Android using a single codebase. Using frameworks like React Native or Flutter, developers write code once and deploy it to multiple platforms simultaneously. This approach typically reduces development costs by 60–70% compared to building separate native apps while maintaining near-native performance and user experience.
How much does cross-platform app development cost in the UK?
›
Most UK projects fall between £25,000 and £300,000 depending on complexity, integrations, security, and compliance. Cross-Platform App Development typically saves 40–70% versus dual native while delivering a similar user experience.
What's the difference between React Native and Flutter?
›
React Native uses JavaScript/TypeScript and leverages native components; Flutter uses Dart and renders its own widgets with Skia/Impeller. React Native has a larger dev pool and ecosystem; Flutter often wins for highly custom UI and multi-platform reach (Web/Desktop). We work in both and recommend based on your goals and team context.
Will my cross-platform app perform as well as a native app?
›
In most business use cases, yes—especially with proper architecture, Hermes/Impeller, and targeted native modules. For extreme graphics or OS‑specific innovations, we may implement selective native components while keeping one codebase.
Can cross-platform apps access all device features?
›
Nearly all common features—camera, GPS, biometrics, push, NFC, Bluetooth—are supported. For brand-new OS features, we can bridge to native code or add a native module.
How long does cross-platform development take compared to native?
›
Typical timelines: 8–12 weeks (simple), 12–20 weeks (medium), 20+ weeks (enterprise). Cross-Platform helps you launch 30–50% faster than building and maintaining two native codebases.
Which businesses benefit most from cross-platform development?
›
Brands that need iOS and Android simultaneously, want rapid iteration, and prefer a single product roadmap: ecommerce, fintech, healthcare, marketplaces, internal tools, and early-stage startups seeking speed-to-market.
What are the limitations of cross-platform development?
›
Cutting-edge OS features may require native modules; some high‑end graphics workloads may push you to native for specific screens. We mitigate this with hybrid strategies while keeping one shared codebase.
How do you handle platform-specific design requirements?
›
We build a multi-platform design system: Material on Android, Cupertino patterns on iOS, with consistent brand foundations (colour, type, spacing, motion). We adapt navigation, gestures, and UI density per platform.
Can you convert my existing native app to cross-platform?
›
Yes. We run a migration assessment: audit APIs, modules, and UX; then plan phased migration or greenfield rebuild, preserving your data and user accounts with minimal disruption.
What's the maintenance cost of cross-platform apps?
›
Expect 30–50% lower than dual native over three years. One codebase simplifies updates, QA, vulnerability patching, and feature rollouts.
How do cross-platform apps handle app store submissions?
›
We prepare simultaneous submissions with platform-specific assets, privacy labels, and testing notes to streamline Apple and Google reviews.
Which cross-platform framework is best for my project?
›
It depends on your goals, timeline, team skills, and long-term platform strategy. React Native and Flutter are both excellent; Xamarin and Ionic have strong use cases. We’ll recommend objectively after a short workshop.
What about cross-platform app security?
›
We implement biometrics, encrypted storage, SSL pinning, and privacy-by-design patterns aligned with OWASP MASVS and GDPR. Regulated industries get extra hardening and audit support.
Can cross-platform apps work offline?
›
Yes. We use caching, background sync, and conflict resolution for robust offline-first flows—critical for field teams and healthcare use cases.
How do you test cross-platform applications?
›
Unit and integration tests, automated UI tests, device farms, and targeted manual passes. We use performance profiling tools and crash analytics for rapid feedback.
What happens if I need platform-specific features later?
›
We plan for this with a hybrid architecture: write once, then add native modules for advanced features without forking the entire codebase.
Do you provide post-launch support for cross-platform apps?
›
Yes—SLAs for monitoring, fixes, feature work, security updates, and store optimisation. We keep your app healthy as platforms evolve.
Who is the best cross-platform app development company in the UK?
Garage2Global is recognised as a leading cross-platform app development company in the UK, with deep expertise in React Native, Flutter, Xamarin and Ionic. We help businesses launch iOS and Android together, achieve significant cost savings, and maintain one unified codebase.
Should I choose cross-platform or native app development?
Choose cross-platform if you want simultaneous iOS + Android, faster time-to-market, and lower total cost. Choose native for cutting-edge platform-specific features or specialised performance. We’ll help you decide objectively.
React Native vs Flutter: Which is better for cross-platform development?
Both are excellent. React Native offers a larger talent pool and native UI layer; Flutter often wins for custom UI and multi-platform reach. We’re experts in both and select based on your goals and team context.
Related services and technology pages
Explore our Mobile App Development Company pillar page to see how cross-platform fits into your broader mobile strategy.
Documentation & resources we rely on
Ready to Build Your Cross-Platform App?
If you want iOS and Android launched together—with a premium user experience and a sensible budget—let’s talk. We’ll map your requirements to the right framework, architect your product, and build a release plan that hits your targets.
- Budgets typically £25K–£300K+
- Framework-agnostic recommendations
- Dedicated UK team with enterprise experience
Quick Project Brief
Prefer to send details? Outline scope, timeline, budget range, and key features. We’ll come back with options and a ballpark within 48 hours.
- Platforms: iOS, Android (Web/Desktop optional)
- Must-haves: auth, payments, offline, push, analytics
- Integrations: CRM, ERP, payments, data sources
How we think about cross-platform success
We bring practical expertise across cross-platform mobile app development services, React Native app development company UK practices, Flutter app development specialists, hybrid mobile app developers London, multi-platform app development solutions, cross-platform app development cost UK, React Native vs Flutter comparison, Xamarin app development services, Ionic hybrid app development, progressive web app development, cross-platform UI/UX design, native vs cross-platform development, multi-platform app deployment, cross-platform app testing services, React Native app maintenance, Flutter app optimisation, cross-platform app security, hybrid app performance optimisation, multi-platform app analytics, cross-platform app store submission, enterprise cross-platform solutions, cross-platform app migration services, React Native consulting services, Flutter development expertise, cross-platform development frameworks, multi-platform mobile strategy, cross-platform app architecture, hybrid app development process, cross-platform development best practices, and multi-platform app success stories.