Cross-Platform app development company
Steer73 is a cross-platform app development company dedicated to building you scalable mobile apps for iOS, Android, web, and other devices faster and more cost-effectively.
Whether you’re launching a new product or modernising an existing app, our London-based team delivers high-performing cross-platform apps without sacrificing user experience or performance.
We build, launch and manage mobile apps for
What is cross-platform mobile app development?
Cross-platform mobile app development is an approach that allows businesses to build a single mobile application that runs across multiple platforms (commonly iOS and Android) using a shared codebase. Instead of developing separate native apps for each operating system, developers use frameworks like Flutter or .NET MAUI to reduce costs, streamline development and accelerate time-to-market.
This method delivers a solid app performance, consistent user experiences, and significant savings in development and maintenance costs, making it ideal for startups, scaleups, and enterprise teams alike.
Benefits of cross-platform app development to your company
Cross-platform development offers the speed, agility, and efficiency your project needs. Here’s why many of our clients prefer it:
Faster time-to-market
Build once, deploy everywhere.
Lower cost of development & maintenance
One codebase means fewer resources required.
Consistent UX/UI
Deliver a unified user experience across iOS, Android, web, and more.
Easier updates
Simultaneous releases and fixes across all platforms.
Access to native features
Modern frameworks allow near-native performance with access to device capabilities.
Scalability & flexibility
Ideal for MVPs, scale-ups, and established businesses alike.
Our cross-platform app development services
We design, develop, and support high-impact cross-platform apps that work seamlessly across iOS, Android, and web platforms. Our services include:
Cross-platform app discovery (free service)
We offer a free Discovery Project to help you move past ideation to a solid development plan. We map out your key business challenges and determine if a cross-platform app can help solve them.
This service helps you to clearly define your goals, evaluate technical approaches, and clarify your app requirements. The result? Documentation outlining a faster, more cost-effective route to building a mobile app that delivers real value for your business.
Product & feature roadmapping
From MVP to long-term feature expansion, we help you shape your product strategy with a clear, prioritised roadmap. We work with you to identify the key features that drive user engagement, align with your business objectives, and support future growth, all tailored to a cross-platform app architecture.
Cross-platform app design & prototyping
Our design-first approach ensures your cross-platform app isn’t just functional but delights users everywhere. We create high-fidelity UI/UX prototypes and interactive mockups that bring your app to life early, so you can test, validate and iterate before development begins.
Cross-platform app development
Using frameworks like Flutter and .NET MAUI, our global team of experienced cross-platform app developers build high-performance apps that deliver the best user experiences across Android, iOS, web and other devices, from a single codebase. This saves you time and budget without sacrificing user experience.
Backend & API integration
We build secure, scalable back-end systems and integrate your mobile app with APIs, third-party services, and enterprise tools. Whether you're connecting to a custom CMS, payment gateway, or CRM, we ensure an easy flow of data across platforms, so your app delivers top performance wherever it's used.
User testing & validation
We can embed usability testing throughout your development process to reduce risk and drive better product decisions. Through prototype testing, beta programs, and structured user feedback, we ensure your cross-platform app is intuitive, functional, and ready for launch.
App support & app store monitoring
Once your cross-platform mobile app is live, we provide continuous support to keep it updated, secure, and fully optimised across platforms. From technical support to app store monitoring, app maintenance and version updates, we make sure your app continues to deliver results long after launch.
App modernisation and improvement
If you have an existing mobile app that’s underperforming or plain outdated, our system modernisation team can help you modernise your app with improved architecture, updated UI/UX, or a migration to a cross-platform framework. We’ll enhance your app’s performance, user experience, and long-term maintainability, with minimal disruption to your business.
Cross-platform app development frameworks we use
Choosing the right framework is key to building high-quality cross-platform mobile applications. At Steer73, we use the leading technologies that offer the flexibility, performance, and long-term maintainability modern businesses require.
Flutter
Flutter is Google’s open-source framework that allows us to build fast, expressive apps from a single codebase. It’s particularly well suited for highly customisable UIs and complex animations, making it ideal for brands that prioritise beautiful user experiences and need to stand out visually. Flutter offers native-level performance, a vast widget library, and reduced time-to-market. Whether you’re building an MVP or a large-scale commercial product, Flutter is an excellent choice for modern cross-platform mobile development.
.NET MAUI
.NET MAUI (Multi-platform App UI) is Microsoft’s latest evolution of Xamarin, offering a unified framework for building native apps across Android, iOS, macOS, and Windows. Ideal for enterprise-grade applications, .NET MAUI allows teams to share business logic, UI components, and integrations across platforms while maintaining high levels of performance and maintainability. If you’re already in the Microsoft ecosystem or require close integration with enterprise systems, .NET MAUI provides the reliability and scalability you need.
Our approach to cross-platform development
We’ve never failed to deliver a project. Here’s our process for ensuring we never do:
User-centred design meets multi-platform strategy
Every successful app starts with the user. We take a human-first approach to cross-platform app development, investing time in user research, journey mapping, and behavioural insights to ensure your app performs beautifully across Android, iOS, and other platforms. This means creating experiences that not only look great but feel consistent and intuitive on every device.
Accelerated development without compromising quality
With our Digital Transformation Platform and frameworks like Flutter and .NET MAUI, we help you build and launch high-performing cross-platform apps quickly and cost-effectively. We keep you fully involved through clear milestones, collaborative workshops, and complete transparency at every stage, whether remotely or in person at our London office.
Long-term value, not just a one-off launch
Launching is only the beginning. We provide continuous optimisation, maintenance, and feature updates to ensure your app stays aligned with the latest OS versions, security requirements, and user expectations. From performance improvements to iterative enhancements, we help your app deliver ongoing value for years to come.
User-centred design meets multi-platform strategy
Every successful app starts with the user. We take a human-first approach to cross-platform app development, investing time in user research, journey mapping, and behavioural insights to ensure your app performs beautifully across Android, iOS, and other platforms. This means creating experiences that not only look great but feel consistent and intuitive on every device.
Accelerated development without compromising quality
With our Digital Transformation Platform and frameworks like Flutter and .NET MAUI, we help you build and launch high-performing cross-platform apps quickly and cost-effectively. We keep you fully involved through clear milestones, collaborative workshops, and complete transparency at every stage, whether remotely or in person at our London office.
Long-term value, not just a one-off launch
Launching is only the beginning. We provide continuous optimisation, maintenance, and feature updates to ensure your app stays aligned with the latest OS versions, security requirements, and user expectations. From performance improvements to iterative enhancements, we help your app deliver ongoing value for years to come.
Here’s how we take your cross-platform mobile app from idea to launch
Our proven delivery process helps you go from idea to a fully deployed cross-platform app efficiently and with minimal risk.
1. Initial project assessment
We begin with a short call to understand your business objectives, technical requirements, and user needs. This helps us identify whether a cross-platform approach (e.g. Flutter or .NET MAUI) is the best fit for your goals and budget.
2. Discovery workshops
Through collaborative workshops, we uncover the problem your app is solving and explore the business case behind it. This phase focuses on understanding functionality at the Epic level and ensures early alignment between user expectations and technical feasibility across platforms.
3. Scoping
We define the required features, integration points, limitations, and technical parameters, laying the foundation for accurate estimation, prioritisation, and phased delivery. By the end of this phase, you’ll have clarity on platform-specific considerations and trade-offs.
4. Solution definition
At this stage, we translate the scope into a detailed blueprint, defining how each feature will function, how shared code will be structured, and how platform-specific UI/UX adaptations (where needed) will be handled.
5. Implementation & development
Using frameworks like Flutter or .NET MAUI, our developers begin building your application from a single codebase. This ensures speed and consistency while reducing development and maintenance costs. You’ll receive regular updates and demos as the project progresses.
6. Testing, UAT & launch
We rigorously test your cross-platform app across devices and OS versions to ensure performance, consistency, and compliance. Once approved, we handle all publishing and optimisation for Google Play, Apple App Store, and any additional platforms.
7. Ongoing support & optimisation
Post-launch, we offer continuous updates, monitoring, and improvements. Whether it's adapting to OS updates, fixing bugs, or rolling out new features, we keep your app running smoothly and delivering value to your users
Why choose Steer73 as your cross-platform app development company
Proven track record, zero failed projects
We’ve been delivering successful mobile apps for over a decade, and we’ve never had a failed project. Our clients can guarantee that we’ve delivered high-performing apps that go beyond launch and deliver long-term value.
Cross-platform specialists
Our team brings deep technical expertise across Flutter and .NET MAUI to ensure you get the right framework for your app, ensuring faster development, lower maintenance costs, and beautiful user experiences across devices.
Custom solutions without the bloat
We help you avoid the risks, cost overruns, and drawn-out timelines typically associated with custom development. Our approach is lean, transparent, and focused on delivering a high-ROI digital product that aligns with your goals and budget.
Trusted by SMEs and global brands
From fast-moving businesses to complex enterprise systems, we’ve built apps that support frontline operations, enable new business models, and streamline customer engagement.
Long-term technology partners
We don’t stop at launch. Our clients often continue working with us for years, evolving their cross-platform apps with new features, performance optimisations, and strategic improvements.
“The attention to detail, clarity, quality and pace which Steer73 deliver customer features is outstanding, which creates a working relationship more akin to a joint venture than a supplier / customer standard.”
Paddy Power
Brody Sweeney
CEO Camile
What our clients have to say
How much does cross-platform app development cost
Every app is different, and cross-platform development offers a unique mix of benefits and trade-offs that can significantly influence cost. The good news? Cross-platform development allows you to save on cost by sharing a single codebase across iOS and Android, significantly reducing time-to-market and long-term maintenance overhead.
Several factors impact the cost of building a cross-platform mobile app:
App complexity
More features, integrations, or user roles = more development time.
Design requirements
Highly customised UI/UX or animations increase effort.
Backend & APIs
Need a custom backend or third-party integrations? That adds scope.
Framework selection
Using either Flutter or .NET MAUI may affect your overall cost.
Security & compliance
Apps handling sensitive data or enterprise systems often require deeper security investments.
Criticality to the business
The more vital the app is to your operations, the more rigorous the build (and testing) process.
Engagement models to suit every project
We offer three flexible engagement models to fit your project size, risk appetite, and delivery preferences:
Fixed price model
- Best suited for clearly scoped, lower-risk projects.
- Waterfall approach with a fixed timeline and deliverables.
Time & materials
- Ideal for Agile development with evolving requirements.
- You define the budget cap, and we adjust the scope accordingly.
Managed service model
- Ongoing product delivery under a fixed budget.
- A full cross-functional team working as your long-term app partner.
1. Initial consultation
A short, no-pressure call with our London team to discuss your goals and offer early cost guidance.
2. Free discovery project
A structured deep dive to define your app’s functionality, timeline, and technical needs.
3. Clear cost plan
With a mapped-out feature set and delivery plan, we help you align your budget with the right framework and approach.
Want an estimate of what your app might cost?
Get in touch, and let’s discuss your project
App development case studies and articles
Retail betting companion app
The sports betting industry has changed the way it does business in recent years. With intuitive digital platforms, they’ve been able to reach a new generation of customers. However, the industry’s retail sector remains a valuable source of revenue and constitutes an important portion of Paddy Power’s customer base.
Taking control of the customer relationship with a custom-built food ordering platform
Having outgrown a 3rd party solution, Camile decided to develop a real competitive advantage by building their own restaurant ordering platform that included at it’s core, a proprietary mobile app.
Where do great products come from?
Discover how successful digital products emerge at the intersection of business needs, user expectations, and technological capabilities. Our proven methodology that has delivered consistent success across complex projects for over 8 years.
Cross platform application FAQs
Cross-platform app development allows you to build a single mobile app that works seamlessly across multiple operating systems, such as iOS and Android, using shared code. This approach saves time and reduces cost compared to developing separate native apps for each platform.
It depends on your goals, budget, and technical requirements. If you need to reach users on both iOS and Android quickly and cost-effectively, cross-platform development is often a smart choice. We can help you decide during a free discovery call.
Native apps are developed specifically for one platform, using platform-specific tools and languages. Cross-platform apps use a shared codebase to run on both platforms. While native apps may offer slightly better performance in specific cases, cross-platform apps provide near-native results and faster development.
We work with Flutter and .NET MAUI. Each framework has its strengths, and we recommend the most suitable one based on your project goals, timeframe, and future plans.
Yes. Using tools like Flutter and .NET MAUI, we can deliver a high-performance app that feels fully native to the user, with smooth interactions and a consistent experience across devices.
The cost depends on factors such as app complexity, the number of features, required integrations, and the level of custom design. We begin with a free discovery phase to help scope the project and provide an accurate estimate.
Yes. Many organisations come to us looking to modernise or streamline their existing mobile apps. We help migrate legacy systems to cross-platform frameworks with minimal disruption.
We conduct extensive QA testing across multiple devices, OS versions, and screen sizes. We also optimise performance, consistency, and responsiveness to ensure your app performs at a high level.
We provide ongoing maintenance, technical support, app store monitoring, and feature updates. Our aim is to ensure your app remains secure, up to date, and continues to deliver value over time.
Absolutely. Cross-platform frameworks are built for scale. Whether you’re adding new features, supporting wearables or tablets, or expanding into new markets, we build with future growth in mind.
Discuss your project
It’s never a bad time to start a conversation. Book a free consultation to:
- Clarify your app vision
- Get expert technical advice
- Receive an indicative roadmap, timeline and budget
Let’s build a app that drives your business forward.
Discuss your project
It’s never a bad time to start a conversation. Book a free consultation to:
- Clarify your app vision
- Get expert technical advice
- Receive an indicative roadmap, timeline and budget
Let’s build a app that drives your business forward.