Mobile App Development — Flutter & React Native, Built Once, Shipped to iOS & Android

Every project is scoped individually because no two app builds have the same screens, integrations, backend complexity or compliance requirements. After a 30-minute discovery call we send a fixed-fee proposal mapped to your commercial outcomes — not an hourly rate. Most engagements sit somewhere between focused MVPs validating a single hypothesis and fully managed cross-platform builds with admin dashboards, payments and complex third-party integrations. Cross-platform frameworks like Flutter or React Native typically reduce cost compared to building separate native iOS and Android apps. The discovery call is free and you get a written proposal regardless of whether we move forward together.

A minimum viable product app typically takes eight to twelve weeks from kickoff to app store submission. A fully featured business app with backend infrastructure, user authentication, payment processing, and third-party integrations usually requires twelve to twenty weeks. Enterprise applications with complex requirements can take twenty to thirty weeks or more. We always recommend starting with an MVP to validate your idea with real users before investing in the full feature set. Every project includes a detailed timeline with fortnightly sprint milestones so you can track progress throughout development. The biggest factor affecting timeline is typically how quickly feedback and approvals are provided during design and testing phases.

For the vast majority of business applications, cross-platform development using Flutter or React Native is the best choice. These frameworks allow us to write one codebase that runs on both iOS and Android, cutting development time and cost by up to 60% while still delivering native-quality performance and user experience. The resulting apps are virtually indistinguishable from those built with platform-specific tools. Native development using Swift for iOS and Kotlin for Android is only necessary for apps requiring deep hardware integration, augmented reality features, or highly specialised platform-specific capabilities. During our free discovery call, we assess your specific requirements and recommend the most cost-effective approach for your project.

Flutter is Google's open-source framework for building cross-platform applications from a single codebase. It compiles to native ARM code, which means your app performs as well as one built specifically for iOS or Android but costs significantly less because we only build it once. Flutter offers smooth 60fps animations, a rich and customisable widget library, hot reload for faster development iterations, and excellent developer tooling. It has a large and active global community with thousands of packages available. Companies including BMW, Google Pay, eBay, Alibaba, and Nubank use Flutter in production. We recommend Flutter for most mobile app projects because it delivers the best balance of performance, development speed, visual quality, and long-term maintainability.

Yes, we handle the entire app store submission process for both the Apple App Store and Google Play Store. This includes preparing store listings, designing promotional screenshots, writing keyword-optimised descriptions, configuring metadata and categories, setting up app signing certificates, and navigating Apple and Google's review processes. We set up developer accounts under your name so you own everything. If Apple or Google request changes during the review process, we handle the back and forth until your app is approved and live. Post-launch, we can manage ongoing app store optimisation to improve your app's visibility and organic download rates.

It depends on your specific use case and business goals. A mobile app makes sense if your customers need offline access, push notification engagement, camera or GPS functionality, biometric login, or a highly interactive and personalised experience that goes beyond what a website can offer. Apps also tend to drive higher engagement and retention rates than mobile websites. For content-focused businesses that primarily need an online presence, a responsive website or a Progressive Web App may be a more cost-effective starting point. Many of our clients have both a website and a mobile app serving different purposes. We help you decide the best approach during our free discovery call based on your specific business needs and budget.

Yes, one hundred percent. Once the project is paid for, all source code, designs, assets, and intellectual property belong to you. We host the code on a private Git repository under your account so you have full access from day one. You retain complete ownership of your app store listings, developer accounts, and all associated credentials. This means you can bring in other developers, switch agencies, or continue development in-house at any time without restriction. We believe in complete transparency and never hold your code hostage or charge ongoing licensing fees for the software we build.

Absolutely. Most of our app clients work with us on an ongoing basis, iterating based on real user feedback and analytics data. We build every app with clean, modular architecture specifically designed to make adding new features straightforward and cost-effective. Our app maintenance packages include a set number of development hours each month for new features, along with OS compatibility updates, bug fixes, security patches, and performance monitoring. We also provide monthly analytics reports so you can make data-driven decisions about what to build next. Your app should evolve alongside your business, and we are here to support that continuous growth.

We choose the backend technology that best suits your app's specific requirements and anticipated scale. For MVPs and simpler applications, Firebase is an excellent choice, providing authentication, real-time database, cloud storage, push notifications, and analytics out of the box with minimal setup time and cost. For more complex applications requiring custom business logic, we build bespoke REST or GraphQL APIs using Node.js with Express or NestJS, backed by PostgreSQL or MongoDB databases. We deploy to AWS or Google Cloud Platform with auto-scaling, load balancing, and CDN distribution to ensure reliable performance under any load. Every backend includes comprehensive API documentation, monitoring dashboards, and automated alerting.

Yes. We work with businesses across the UK and internationally. Mobile app development lends itself particularly well to remote collaboration. Our project management process includes regular video calls, shared project boards, fortnightly sprint demos where you see working features in action, and access to staging builds you can install directly on your own device throughout development. Whether you are in London, Manchester, Edinburgh, Bristol, or overseas, we deliver the same quality of work and level of communication for every client.

Mobile app maintenance is an ongoing investment that most businesses underestimate. After launch, you will need to budget for regular updates to keep your app compatible with new iOS and Android releases, which Apple and Google push annually. Maintenance is offered as a tiered monthly plan that covers operating system compatibility updates, bug fixes, performance monitoring, server costs, and minor feature improvements. More comprehensive tiers add new feature development, analytics reviews, and priority support, scaling with the complexity of your app. We recommend budgeting 15 to 20 percent of your initial development cost annually for maintenance to keep your app secure, fast, and competitive.

Yes, and this is a common request from businesses that already have a successful website and want to extend their reach to mobile users. There are several approaches we consider depending on your goals and budget. A Progressive Web App converts your existing website into an app-like experience that works offline and can be installed on home screens. A hybrid app wraps your website in a native shell with access to device features like push notifications and camera. A fully native rebuild using Flutter or React Native delivers the best performance and user experience but requires building the app from scratch alongside your website. During our free discovery call, we will assess your current website and recommend the most cost-effective approach.

Flutter and React Native are both excellent cross-platform frameworks that let us build one codebase for iOS and Android simultaneously. Flutter, developed by Google, uses the Dart programming language and renders its own UI components, giving you pixel-perfect control over every visual element across platforms. It tends to deliver slightly better performance and more consistent designs. React Native, developed by Meta, uses JavaScript and relies on native platform components for rendering, which can make it easier to integrate with existing web development teams. At Cambria Digital, we recommend Flutter for most new projects because of its superior performance, beautiful animations, and growing ecosystem. However, if your business already has a React-based website and wants to share code between web and mobile, React Native may be the better strategic choice.