Can you build an AI chat interface or a copilot in React?

Yes. We build streaming chat, in-app copilots, agent consoles, and dashboards over model output using the Vercel AI SDK, AI Elements, assistant-ui, and CopilotKit. Generative UI in production means tool invocations that render live components inside the response. Orchestration and evaluation behind the interface run under our ADLC. Provider choice stays yours, and swapping models is a configuration change.

Do you build the backend too, or only the React frontend?

Both. React is the frontend of products we build end-to-end, with backends in Node.js, Java, Ruby on Rails, .NET, or Python. We also take frontend-only engagements against APIs your team already maintains. Full-cycle delivery includes business analysis, design, QA, and security review from the same team.

Do you work with React 19 and Next.js?

Yes. We build on React 19, which includes the React Compiler for automatic memoization and stable Server Components, along with the Actions API for form handling. Next.js handles server-side rendering, routing, image optimization, and Core Web Vitals for production applications. TypeScript runs across the codebase. We also upgrade existing React 17 and 18 applications to 19.

What backends work well with React?

React talks to any backend over HTTP, so the question is which one fits your team and workload. We pair it with Node.js, Django, Ruby on Rails, Express.js, .NET, Spring Boot, Firebase, and GraphQL APIs. The decision usually comes down to the team's existing skills and integration requirements.

How much does it cost to develop a React web app?

The cost of a React project depends on scope, feature complexity, number of integrations, and team size. Small projects and MVPs start from around $20,000. Mid-size web applications and dashboards typically run $50,000 to $100,000. Large or long-running products are those that exceed $100,000. Send us your requirements for a specific estimate, or use our cost calculator.

How does React help reduce development costs?

React reduces cost through component reuse and shared code with React Native for mobile. Teams build a component once and use it across screens and products. The hiring pool is deep, which keeps staffing costs competitive and reduces the risk of a project stalling when someone leaves.

What are the key considerations when choosing a React.js development company?

Look for delivered React projects you can inspect, engineers you can talk to before signing, and reviews on independent platforms such as Clutch, Techreviewer, GoodFirms, and TechBehemoths. Ask who owns architecture decisions and what happens when requirements change. Ask whether the same company can build your backend, or whether you will be coordinating two vendors.

Custom React.js Development Services

Our React.js development services

We work as a React.js development company across the full application, from a single frontend built against your existing APIs to a product we design, build, deliver, and maintain end-to-end.

Full-cycle web development

We run the whole build, from business analysis and UI/UX design through the React frontend, the backend, QA, and release.

Custom React web development

We build React applications around your workflows rather than a template. Modular architecture and typed component APIs keep the codebase workable long after the first release.

React frontend development

We build the frontend against your existing APIs and design system. You get accessible interfaces measured against Core Web Vitals, with TypeScript throughout.

React Native mobile development

We deliver iOS and Android apps from a single React Native codebase, adding native modules where the product requires them. Your team reuses React skills and component patterns across web and mobile.

React UI/UX design

Our designers work in the same sprint as the engineers, so components and their edge-case states get designed once. You receive a design system that your own team can extend.

Single Page Application development

We build SPAs where load time and interaction speed decide adoption: SaaS consoles, internal tools, marketplaces, and collaboration apps. Route-level code splitting and data caching keep them fast as the feature set grows.

App migration to React

We migrate legacy AngularJS and jQuery frontends to the React module by module, running the old and new interfaces side by side during the transition. We preserve existing functionality and improve load performance and Core Web Vitals as we go.

React consulting

We review architecture, state management, rendering performance, and build tooling, then hand you a ranked plan with effort estimates. Teams use it before a rebuild decision or after a handover.

Architecture building

We define module boundaries, the state model, the data-fetching strategy, and the rendering approach before delivering the first feature to support future scalability.

Backend integrations

We design and consume REST and GraphQL APIs and connect React to your databases, message queues, third-party services, and event streams. Our backend engineers work in Node.js development, Java development, Ruby on Rails development, and .NET.

Maintenance and support

We keep shipped React applications up to date: React and dependency upgrades, security patches, performance work, and new features, on an agreed monthly cadence.

Audit and rescue mission

We take over stalled React projects. You get an audit of the code and architecture, plus a ranked list of what to fix first, and the same team can execute the fixes.

React.js solutions we develop

React runs the interface layer of most application types we deliver.

Since 2012, we’ve been building these six categories often enough to have opinions about each.
If your project doesn’t fall under either of the following categories, we’ll scope it the same way, starting with analysis and architecture before anyone writes a component.

Web applications

Mobile applications

IoT applications

Single-page applications

Business applications

Web applications

We develop web applications that load quickly on typical connections and remain responsive as data volumes grow. React handles the rendering; our business analysts decide what belongs on the screen in the first place.

Web development

Mobile applications

With React Native, we build cross-platform apps for iOS and Android from a shared codebase, which cuts duplicated work and keeps behavior consistent between platforms.

Mobile development

IoT applications

We build React dashboards and control panels for connected devices: live telemetry, alerting, historical playback, and remote command. The same rendering patterns apply to dashboards built on model output, as covered further down this page.

Internet of Things development

Single-page applications

SPAs keep the user within a single interface across multiple interactions, without full-page reloads. E-commerce frontends, SaaS platforms, internal admin tools, and collaboration apps are the usual candidates.

Business applications

We build internal systems that replace spreadsheets and aging desktop tools. Every engagement opens with a business analysis of the workflow, participants, data, and exceptions, so the software matches how the work is actually done.

Enterprise software development

Solutions for every business size

Enterprise software

We build React applications that support large user bases and complex permission models, integrated with the systems your business already runs on. Rollouts happen in stages, so existing operations keep running through the transition. Security review and access control are part of the build, not a phase bolted on at the end.

Software for SMBs

For small and mid-sized companies, we build React applications sized to the challenge: a customer portal, an ordering tool, a reporting console, and a partner dashboard. Scope stays narrow, and the first release arrives in a couple of weeks.

Startup MVPs

We help founders get a working product in front of users and investors. That means a scoped feature set and a frontend backed by real data, in a codebase that a future in-house team can take over without a rewrite. We advise on what to cut to reach launch faster.

Modern React in 2026

Component-based architecture

React breaks an interface into small components with defined inputs and outputs. Teams reuse them across screens and products, and a change in one place propagates predictably.

Performance and scalability

React updates only the parts of the interface that changed. Combined with code splitting, lazy loading, route-level prefetching, and query caching, applications stay responsive as feature count and user load rise.

Ecosystem and talent pool

Meta maintains React, and the surrounding ecosystem is the largest in frontend development. That matters commercially: libraries exist for most problems, and the hiring pool is deep in every market where you might staff a team.

Server rendering and SEO with Next.js

Next.js gives React server-side rendering, static generation, file-based routing, and image optimization. Content-facing React applications get indexed properly and score well on Core Web Vitals.

Cross-platform reach with React Native

The same component model and engineers extend to iOS and Android via React Native, turning a web investment into a mobile one.

Faster delivery

Component reuse and a mature library ecosystem shorten the path from design to delivery, directly impacting project cost.

React: the frontend of AI products

The model is one half of an AI product. The interface is the other half, and in most web products, that interface is React. We build that layer: chat that streams token by token; in-app copilots that read and act on the surrounding screen; generative UI that returns live, interactive components inside the response; agent consoles that show what a system is doing and let a human intervene; and dashboards built over model output.

The stack

We build these interfaces with the Vercel AI SDK, which provides a single provider-agnostic interface across OpenAI, Anthropic, Google, and others, so swapping models is just a configuration change. We use AI Elements for prebuilt interface components and assistant-ui for chat surfaces. CopilotKit comes in where the product needs an in-app copilot or an agent that can act on application state.

Governance

Orchestration, tool calling, evaluation, and cost control are behind every one of these interfaces. We govern them through our Agentic Software Development Lifecycle (ADLC), which defines how we version prompts, permission tools, measure output quality, and catch regressions before a release reaches users. The same discipline applies whether the work is AI software development, AI agents, or RAG development.

The bridge

We have built React dashboards for years using live sensor data in our IoT work. A dashboard for model output raises the same questions: how to show confidence and what a user should do when the data looks wrong.

When to choose React, and when not to

React is the right call when you need the deepest ecosystem, the largest hiring pool, or complex client-side interactivity, and it carries the lowest long-term staffing risk of the four options below. In 2026, the harder decision is often the meta-framework rather than the library: Next.js, Nuxt, SvelteKit, and Astro differ more from each other than React differs from Vue.

Choose	When it fits	Notes
React (with Next.js)	Complex client-side interactivity, long-term hiring safety, AI interface layers, large component reuse across products	Most-used web technology among professional developers at 46.9% (Stack Overflow Developer Survey 2025). Next.js adds server rendering and SEO
Vue (with Nuxt)	Gentler learning curve, strong TypeScript ergonomics, incremental adoption inside pages you already have	The other low-risk choice. 18.4% professional usage in the same survey
Angular	Large enterprise teams that want one opinionated framework with routing, forms, testing, and dependency injection included	TypeScript is mandatory, which helps keep large codebases consistent. 19.8% professional usage
Svelte (with SvelteKit)	Smallest bundles, or a performance-critical build, where a smaller ecosystem is acceptable	Highest satisfaction scores of the four, with the smallest hiring market at 6.9% professional usage

React.js and React Native: difference

React.js is a JavaScript library for building web user interfaces. React Native is a framework for building iOS and Android applications, built on React and using the same component model. Engineers move between them, and a large share of application logic moves with them.

	React.js	React Native
Builds	Web applications and PWAs	iOS and Android applications
Renders to	The browser DOM	Native platform components
Styling	CSS, Tailwind, CSS-in-JS	StyleSheet API, no CSS cascade
Navigation	React Router or Next.js routing	React Navigation
Ships as	A URL	App Store and Google Play builds
Shared with the other	Components, hooks, state patterns, TypeScript	Components, hooks, state patterns, TypeScript

React.js complementary tech stack

React handles the interface, so it always ships alongside other technology. This is what we run in production around it.

Frontend

AI foundational models

Back-end

Database development

DevOps and cloud

Advanced tech we use with React.js

AI development

We connect React frontends to language models, retrieval systems, vector stores, and custom models, and we build the interface patterns that make model output usable: streaming, citations, confidence display, and human review steps.

AI development

IoT development

We build React dashboards and control panels for connected devices across manufacturing, logistics, healthcare, and agriculture, with live data, alerting, and remote command.

IoT development

Big Data development

We build data processing systems and the React visualization layer on top of them. Charting large result sets without freezing the interface is an engineering problem in itself, and we solve it with virtualization and incremental rendering.

Big Data Services

Process of developing software with React.js

We work in two-week iterations and deliver working software at the end of each one. Steps one through four repeat until the scope is complete, after which we move to release.

Requirements elicitation

We document what the software must do and for whom through workshops with your stakeholders. This produces user stories with acceptance criteria, plus a validated scope you sign off on before development starts.

UI/UX design

Our designers research your competitors and your users, then produce wireframes and interactive prototypes. Designs undergo iterative review with your team, and the final specifications are sent to the developers as documented component states.

Development

Engineers build the React frontend and the backend in parallel against the agreed-upon interfaces. Every feature gets code review, and our tech lead reviews architecture-level decisions before they reach the main branch.

Testing

QA runs through each iteration, covering manual testing, automated test suites, usability checks, performance measurement, and security testing, all wired into CI/CD pipelines.

Release

We deploy to the web or to app stores, then deliver a final report and obtain your confirmation to launch. Knowledge transfer and monitoring setup happen here, so your team can operate what we built.

Maintenance & support

After launch, we monitor the application, resolve issues, upgrade framework and dependency versions, and build new features. You get regular reports on performance and system health.

Recent software we made

Traditional tech stack

The system has produced a significant competitive advantage in the industry thanks to SumatoSoft’s well-thought opinions.

They shouldered the burden of constantly updating a project management tool with a high level of detail and were committed to producing the best possible solution.

Alexander McCaig

Co-Founder & CEO, Tartle

Rivalfox had the pleasure to work with SumatoSoft in building out core portions of our product, and the results really couldn’t have been better.

SumatoSoft provided us with engineering expertise, enthusiasm and great people that were focused on creating quality features quickly.

Paul S. Chun

CTO, Rivalfox GmbH

We tried another company that one of our partners had used but they didn’t work out. I feel that SumatoSoft does a better investigation of what we’re asking for. They tell us how they plan to do a task and ask if that works for us. We chose them because their method worked with us.

Damian Gevertz

Founder & CEO, Widgety

They are very sharp and have a high-quality team. I expect quality from people, and they have the kind of team I can work with. They were upfront about everything that needed to be done.

I appreciated that the cost of the project turned out to be smaller than what we expected because they made some very good suggestions. They are very pleasant to work with.

Michael Karbushev

Senior Director of Engineering, Evolv

SumatoSoft succeeded in building a more manageable solution that is much easier to maintain.

Yevgeniy Rozenblat

Program Manager, TL Nika

All Reviews

Engagement models

We work under three engagement models, each with its own pricing structure. The labels below match our engagement models page.

Project-based development

We take responsibility for delivery from planning through deployment. You act as a stakeholder: you provide the initial input, review the work, set product direction, and sign off on releases. Three pricing models apply:

Time & Materials (T&M): Monthly billing against hours actually worked, with scope and budget open. Suits medium and long engagements.

Fixed Price: Billing against a pre-agreed sum, with scope and budget both locked. Suits short projects with a clear specification.

T&M with Cap: Billing against hours worked, with a not-to-exceed limit on the total. Scope stays flexible under a fixed ceiling. This is our most-used model.

Staff augmentation

We place React engineers into your team while you keep project control.

Time & Materials: You pay for the hours our engineers actually work.

Fixed Price: An agreed number of hours per month, reserved for you.

Dedicated Team

We assemble a full-time React team that you manage directly, billed at a predictable monthly cost for the roles you define.

Cost ranges

These are indicative ranges.

Your estimate depends on scope, complexity, the number of integrations, and team size.

Get a free quote or run the numbers yourself with our software development cost calculator.

See full details on our engagement models.

Project tier	Indicative range	Typical fit
Small / MVP	from ~$20,000	Clear-scope SPA or MVP interface
Mid-size	~$50,000 to $100,000	Multi-feature web app or dashboard
Large/ongoing	$100,000+	Complex product or long-term build

Why choose SumatoSoft for React.js development?

We have delivered 350+ custom solutions over 14+ years, and React has been our primary frontend technology for most of that time. Two things separate us from a frontend shop:

Full-cycle delivery: Business analysis, UI/UX design, QA, and security review are in-house, so the React frontend comes with a specification someone has thought through and a test suite someone maintains.
Backend breadth: React is the frontend of a product we can build all the way down, in Node.js, Java, Ruby on Rails, or .NET.

Working with us, you get:

React engineers backed by 14+ years of company delivery history
350+ delivered projects across 25+ countries
70% senior-level engineers on the delivery team
ISO 27001 and ISO 9001 certified processes
An NDA signed from day one
Business value as the delivery measure, agreed before the first sprint

Awards & Recognitions

At SumatoSoft, our commitment to excellence and Client success has earned us recognition from leading industry analysts worldwide. Acknowledged among the top software development companies, we take pride in delivering high-quality React.js solutions that drive real business value.

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Frequently asked questions

How do you handle security during React.js development?

Security in React work covers authentication, authorization, data handling in the browser, and the dependency supply chain. We apply OAuth or JWT authentication, sanitize rendered content, keep secrets server-side, and run dependency audits in CI. Our processes are ISO 27001 certified, and we sign an NDA before the first call about your architecture.

How do you ensure that the final product is scalable and future-proof?

Scalability in a React application comes from module boundaries, state architecture, data-loading strategy, and caching policy, all of which are decided before the feature count grows. We define those first, then apply code splitting, lazy loading, and query caching. We build API-first, so the frontend and back end can evolve at different speeds without a rewrite.

Can I hire a full-time React developer?

Yes. Our staff augmentation and dedicated team models place React engineers with you full-time, under your management, on a monthly contract. Staff augmentation is well-suited to filling a skill gap. A dedicated team suits ongoing capacity, with a minimum of three months. Both draw from the same engineering pool as our project work.

When should I choose React over Vue, Angular, or Svelte?

React fits when you need the largest ecosystem, the deepest hiring pool, complex client-side interactivity, or an interface layer over AI models. Vue suits teams wanting a gentler learning curve or incremental adoption. Angular suits large enterprise teams that want one opinionated framework. Svelte suits performance-critical builds where a smaller ecosystem is acceptable. See the comparison table above for the details.

What are some disadvantages of React?

React is a library rather than a full framework, so architectural decisions land on your team. Release cadence means periodic code adjustments. Search indexing requires server-side rendering, typically with Next.js. Complex state management has a real learning curve. We say this because the trade-offs are worth knowing before you commit.