Built for real users
Sign-in flows, roles and permissions, and screens designed around the tasks people come to do.
Web App Development Agency
Web app development that ships real products
Spreadsheets, plug-ins and no-code patches stop working once real users show up. MDX is a web app development agency: we build custom web applications and SaaS products on React and Next.js, with logins, dashboards, integrations and APIs, so the product holds up when people depend on it.
Recognition for design and craft 
Step 1 of 7
60 seconds total
About your goals
What's the main thing you need your web app to do?
What to build
What do you most need built?
Where you're at
How far along is the product?
Timeline
When do you want it live?
Investment
What budget range are you working with?
About you
What best describes you?
Last step
Where do we send your web app plan?
Phone
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Your result
Nice work, there. here's your fit
Custom Web App Build
Perfect, there, your full proposal is on its way to your inbox. We'll follow up within 24 hours.
View our work 35 case studies published
$6k custom builds from
24h reply to every enquiry
The Solution
Web applications built around how your users work
MDX designs and engineers web apps in one team. You get a clear interface, a solid back end and the integrations your product depends on, from a single group accountable for all of it.
Planning a marketing site instead? See custom web development. Building for iOS or Android? See app development.
Built to grow
A structure that takes new features and more users without a rewrite.
Built to connect
APIs and links to the payment, email, CRM and data tools your product relies on.
Spreadsheet Sprawl Clunky Logins Lost Users Brittle Plug-ins Stalled Roadmap No-Code Limits
The Problem
Your product idea is stuck in tools never built for it
Spreadsheets, stitched-together plug-ins and no-code workarounds get you started, then slow every release. The product your users need deserves proper engineering.
GET STARTED Our Process
From Spec to Shipped, One Milestone at a Time
A web app is never finished in one go, so we build it in pieces you can try.
We scope the product
A short working session on your users, their key tasks and the must-have features. We agree what the first release contains and what can wait.
We design and engineer
Interface design and React and Next.js development move together, with a working preview at the end of every milestone.
We launch and iterate
The app goes live after end-to-end testing, and we stay available for fixes and the next round of features.
The Outcome
A web app isn't a side project. It's the product itself
Whether customers log in to it or your team runs on it, it deserves the care you give the rest of your business. See what we built for Genesis FX Markets: a client trading dashboard designed together with its marketing website.
Why Us?
Anyone can code a demo. Few can ship a product people rely on.
Plenty of teams hand over code and move on.
We stay for the roadmap.
Off-the-shelf: Hit-or-miss
Interfaces designed
Interfaces designed
around real tasks
Built from scratch
for your workflow
Clean structure,
easy to extend
We stay. We
iterate.
Features chosen
by usage
Our Craft, Your Expression.
Your product should be earning its place right now. Let's scope it.
Book a free strategy call and we'll map the web app you need, the first release worth shipping, and a realistic route to it. Custom builds start at $6k. You get an exact quote after a quick call. Plain answers, no pressure.
GET STARTED
Impact & Scale 01 35 Case studies published 02 $6k Custom builds start here 03 24h Reply time on every enquiry 04 6–12 Weeks to a first release (MVP)
BY THE NUMBERS
A few facts you can check yourself: what we have published, what a build costs to start, and how fast we reply.
Testimonials 
LEAVE A REVIEW 
Don't take our word for it
35 projects
Every one has a published case study on our projects page.
Trusted by founders and brands
MDX understood our brand before we even finished explaining it. They turned EATnaked into a site that feels as clean and honest as the product itself: fast, beautiful, and effortless to navigate. Working with them felt less like hiring an agency and more like adding a team that actually cared.
We needed a site that made us look as solid as the work we do, and MDX delivered exactly that. The whole process was smooth, professional, and on time. Our new website finally matches the quality of our service, and clients notice the difference the moment they land on it.
The level of craft MDX brought to Prevvi was on another level. They didn't just build what we asked for. They pushed the design further than we imagined and made it feel premium end to end. Genuinely impressed with the attention to detail and how easy they were to work with.
MDX took a complex product and made it feel simple and trustworthy for our users. The design is sharp, the experience is seamless, and they hit every deadline along the way. They became a real extension of our team, exactly the kind of partner you want when the details matter.
FAQs
What You're Probably Wondering
01 How much does custom web application development cost?
What moves the cost most is scope: how many user roles the product has, which systems it connects to, and how much custom logic sits behind each screen. Custom builds start at $6k. You get an exact quote after a quick call.
02 How long does it take to build a web application?
A focused first release (an MVP) usually ships in 6 to 12 weeks. Larger products are built in milestones, and each milestone ends with a working preview you can click through, so progress is visible long before launch.
03 What does a web application development company do?
It turns a product idea into software people can sign in to and rely on: scoping the features, designing the interface, building the front end and back end, connecting other systems, launching, and supporting it afterwards. At MDX one team covers design and engineering, so nothing gets lost between the two.
04 What is the difference between a website and a web app?
A website mostly publishes information. A web app lets people do things: sign in, manage their own data, run workflows or pay. If you mainly need pages that attract and convert visitors, see our custom web development service. If you need accounts, dashboards and logic behind them, you are in the right place.
05 What kinds of web apps can you build?
Customer portals, SaaS products, internal tools, admin panels and client dashboards. For Genesis FX Markets we designed the marketing website and the client-facing trading dashboard as one system, with balances, equity and performance visible at a glance. You can read the Genesis FX Markets case study.
06 Which technologies do you build web apps with?
We build with React and Next.js, together with the back end, APIs and integrations the product needs. We confirm the stack with you on the first call, based on what you are building, who will maintain it and which systems it has to connect to.
07 Do you build SaaS products and MVPs?
Yes. We work with founders on SaaS products from the first release to a multi-role platform. We start with the smallest release that proves the idea, then add features in stages as real usage shows what matters.
08 Can the app connect to the tools we already use?
Yes. We connect web apps to other systems through APIs, such as payment, email, CRM and data services, and we build APIs of our own when other systems need to talk to your app.
09 Can you rebuild or extend an existing web app?
Yes. We review what is live, agree what to keep, and then rebuild or extend it in stages, so your users are never left with a half-finished product. If you want a native iOS or Android app instead, see our app development service.
10 Do you offer support after launch?
Yes. After launch we stay available for fixes, monitoring and new features, and we agree the support scope with you while planning the project.
Articles
Notes on
Notes on
building web apps
that last.
Practical reading on web application development: scope, cost, architecture and how to choose a team.
GO TO OUR BLOG
How Much Does a Custom Web App Development Cost? A Web App Development Agency Breakdown
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Custom Web Application Development: Complete Guide for Startups
Custom Web Application Development: Complete Guide for Startups Custom web application development is the process of...
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How to Evaluate a Web Application Development Agency for a Complex Build
Choosing a web application development agency for a complex product is rarely a design decision and never just a proc...
READ MORE: How to Evaluate a Web Application Development Agency for a Complex Build
Ready to scope your web app?
Book a free strategy call and we'll map the first release worth shipping. Custom builds start at $6k.
GET STARTED"At our core, we craft products that blend art direction, modern interfaces, and seamless technology into meaningful digital experiences."
Trusted by ambitious founders and brands
