React Development UK: Interactive Web Apps, Dashboards and Next.js Sites

When React is the right tool

React is a JavaScript library for building user interfaces out of components. It shines when a page behaves more like an application than a document: lots of user input, instant feedback, data changing as you watch. Typical examples are:

• Product configurators and quote builders where the price updates as options change.
• Dashboards with filters, charts and live data.
• Multi-step forms and booking flows with validation at each step.
• Web application front ends where staff spend their whole day.

For a mostly static marketing site, React can be more than you need. A server-rendered site with a sprinkle of JavaScript is often faster and cheaper. We will tell you if that is your situation. When a site needs both great content and rich interactivity, Next.js gives us the best of both.

The React stack we use

• TypeScript throughout, so component props and API responses are checked before the code runs.
• Vite for single-page applications that sit behind a login, such as admin systems and portals.
• Next.js where pages need to be indexed by search engines or load fast for first-time visitors, using server rendering, static generation and React Server Components.
• TanStack Query for fetching, caching and refreshing server data, which removes a lot of hand-written loading and error state.
• React Hook Form with Zod for forms, sharing validation rules with the API where possible.
• Tailwind CSS or CSS modules for styling, with a shared component library for consistency.
• Vitest, Testing Library and Playwright for unit, component and end-to-end tests.

React 19 is the current major version. It brought Actions for handling form submissions and pending states, and made Server Components stable for frameworks like Next.js.

Moving off Create React App and older React

Many business apps were started with Create React App. In February 2025 the React team announced that Create React App was deprecated for new apps and recommended moving to a framework or a build tool such as Vite. Apps still on it are running on build tooling that is no longer actively developed, often with outdated dependencies flagged by security audits.

We migrate these apps in stages: move the build to Vite, update React and its dependencies, convert class components to function components with hooks where it helps, and add TypeScript gradually. The app keeps working at every step, and we add tests around the screens your team relies on most.

Performance and accessibility

A React app can feel slow for reasons that have nothing to do with React itself: too much JavaScript sent up front, data fetched in a waterfall, or components re-rendering far more often than they need to. We measure with browser profiling and Core Web Vitals, then fix the causes:

• Split code by route so users download only what the current screen needs.
• Fetch data in parallel and cache it, so moving between screens is instant.
• Render long tables and lists virtually, so ten thousand rows do not freeze the browser.
• Server-render public pages with Next.js so content appears before JavaScript finishes loading.

Accessibility is part of the same job. We use semantic HTML, proper labels and focus management in modals and menus, and test with keyboard and screen reader against WCAG 2.2 AA. It is a legal expectation for many organisations and it makes the app better for everyone.

Front end and back end together

A React interface is only as good as the API behind it. Because we also build the back end, in Laravel or Node.js, one team owns each feature end to end. API responses are shaped for the screens that use them, validation rules match on both sides, and you are not stuck mediating between a front-end agency and a back-end agency.

If you need a mobile app too, React Native lets us share skills and some logic with the web app. See mobile app development.

Starting a React project

Tell us what the interface needs to do, who uses it and what data it works with. After a free chat we scope screens, user journeys and integrations, and give you a fixed-price quote. Bigger builds are phased, each phase with its own fixed price, so you have something working early. You own all the code. Get in touch.

What we deliver

• React front ends for web applications and customer portals
• Next.js websites and storefronts with server rendering and good Core Web Vitals
• Interactive tools: configurators, calculators, booking flows, multi-step forms
• Live dashboards with charts and filters, fed from your APIs
• Migration from Create React App or old class components to modern React
• Component libraries and design systems shared across your products

How it works and what it costs

Every project gets a fixed-price quote after a free initial chat and a short scoping stage. You own the code and the data.

1. Free chat

   Tell us the problem in plain English: what you do now, what goes wrong and what "better" looks like. No charge, no obligation.

2. Scoping

   We map the processes, systems and data involved, agree what is in and out, and write it down so there are no surprises.

3. Fixed-price quote

   You get a fixed price for the agreed scope, or a phased plan for bigger builds, so you can start small and prove it works.

4. Build and test

   We build in short stages you can see and try, test against real data, then go live carefully with a rollback plan.

5. Hand over and look after

   You own the code and the data. We can host it, support it and keep improving it, or hand it to your own team.

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