Web App Development Company, Built to Perform.

We are Arch, a web app development company UK businesses have trusted since 2005. We design and build custom web applications, customer portals and SaaS platforms, engineering-led, with design, product and delivery in one team.

A web application is software you run through the browser to get a job done. A brochure website tells people who you are; a web app lets them do something, whether that is booking, buying, managing an account or running an operation.

Custom software sits wider again, often reaching into back-office and desktop systems. As website and app developers we build all three, so we can be honest about which one fits.

The UK software development industry is worth an estimated £49.5 billion in 2026, spread across more than 29,000 businesses, according to IBISWorld, and the UK digital transformation market is put at $70.86 billion in 2026, growing at 14.62% a year by Mordor Intelligence.

A short version of who you would be working with:

• Twenty years building web and mobile software, since 2005
• Rated 4.7 out of 5 on Clutch by verified clients
• Teams in Gateshead, Edinburgh and London
• Design, engineering and product under one roof

Most web app development work falls into a handful of recurring shapes. Here are the ones we build most, grouped by the job they do for your business.

Customer portals

Secure, login-based portals where your customers manage accounts, orders, documents or bookings, cutting the phone calls and emails your team fields every day.

SaaS platforms

Multi-tenant, subscription-ready web apps built to scale. The global software-as-a-service market is set to reach $267.94 billion in 2026, according to The Business Research Company, and we build products designed to earn a place in it.

Internal and operational tools

Workflow tools, admin systems and dashboards that replace spreadsheets and manual steps. This is the kind of enterprise app development that saves hours across a team.

Data dashboards

Live reporting and analytics apps that pull numbers from across your systems into one view, so decisions run on current data rather than last month's export.

Booking and marketplace systems

Two-sided platforms, booking engines and payment-enabled apps that handle real transactions, real users and real edge cases from day one.

API integrations and AI tools

Apps that talk to your CRM, ERP and payment gateways. Here is API integration explained, plus AI software development where it earns its place.

Every web application development UK project moves through the same six stages, so you always know where the project is and what is next.

1. Discovery

We map what you need, who it is for and what success looks like, ending with a full scope of work and wireframes before any code is written.

2. UX and prototype

High-fidelity design turned into a clickable prototype you can review and shape, so you build the right thing once.

3. Build

Engineering in short, visible iterations you can follow, with front end, back end and integrations coming together in the open.

4. QA and testing

We check accessibility, performance and security before launch.

5. Launch

We deploy to your cloud environment and hand over a working, documented application.

6. Support

We stay on to maintain, monitor and improve the app once it is live.

Web apps are priced from their scope rather than a rate card. The figure moves with the features you launch with, whether it is a single app or a full platform, the depth of design and discovery, and the integrations underneath.

The global custom software development market is projected to grow to $65.85 billion in 2026, up 22.1% on the year, according to The Business Research Company.

Your project should still be scoped on your goals rather than an industry average. If you want a sense of the drivers first, we have written up how much an app costs.

On timelines, a smaller portal or internal tool can be ready within weeks of discovery closing; a larger SaaS platform runs longer. You will have firm dates in your blueprint before development starts, and a short call is enough for a first estimate.

Our web work runs from retail platforms and construction software to customer portals and patient-facing apps. There is a good chance we have built a close cousin of your idea, and the discipline of the big projects comes with us to the small ones.

We have been the web app developers UK businesses turn to since 2005, and we judge our work by what your software changes once it is live.

Security and data protection

Security and UK GDPR handling are built in, then checked during QA. We design data handling around compliance from the start, and can talk through the specific controls your sector needs.

Honest about scope

If a smaller build would prove the idea, we will say so. A web app development company that is willing to lose the wrong sale is one you can trust with the right one.

What is the difference between web app development and ordinary web development?

Ordinary web development produces pages that inform. Web app development produces software that does a job through the browser: users log in, enter data and complete tasks.

We build both and help you pick the right one in discovery.

How much does it cost to build a web app in the UK?

We quote each custom web application development project rather than publish prices, because feature count, platform scope and integration depth move the figure more than anything else. A short call gets you a real number with no obligation.

How long does a web app take to design and build?

Discovery comes first and ends with a blueprint that includes your build timeline, so you know your dates before development starts. Smaller tools are quicker than platforms; the cost and timeline section above gives the honest range.

Do I own the source code and IP once the project is delivered?

Yes. When we hand over your web application, the source code and intellectual property belong to you.

You are never locked in to Arch to keep your own software running, which is a real concern for B2B buyers and one we answer plainly.

What technologies and frameworks do you use?

React and Vue on the front end, PHP and Laravel on the back end, Flutter where a native mobile app is needed, and cloud-native hosting that scales. The tech stack section above explains why each is chosen.

What is a progressive web app, and is it right for my business?

A progressive web app runs in the browser but behaves like a native app: installable, fast and able to work offline. The progressive web apps market is estimated at $3.14 billion in 2026, growing over 30% a year, according to Research Nester.

It suits businesses wanting an app-like experience without two separate builds.

Can you build an e-commerce or SaaS web app?

Yes to both. We build subscription-ready SaaS platforms and payment-enabled e-commerce apps.

It is a large market: the UK e-commerce sector is worth an estimated $317.33 billion in 2026, with smartphones now 54.12% of B2C value, according to Mordor Intelligence, so we build mobile-first.

What ongoing support and maintenance do you provide after launch?

Monitoring, security patches, updates and new features as you grow, under a support arrangement sized to your app. We build it, and we keep it healthy.

Do you work with clients across the UK?

Yes. Most of a project runs remotely with regular check-ins, so where you are based rarely changes how we work together.