Customer portals and member areas
Secure areas where customers sign in to see orders, documents, bookings, invoices or project status, and handle routine tasks without emailing your team.
Full-stack web apps · React, Node.js, .NET
Web Application Development for Portals, Internal Tools and PWAs
Web application development for businesses that need software, not just pages. We design and build customer portals, booking engines, internal tools and real-time apps that run in any browser and connect to the systems you already use.
Wix Legend Partner · 2,000+ projects since 2014 · 1,400+ client reviews
What is web application development?
Web application development is building interactive software that runs in a web browser: customer portals, booking systems, internal tools, marketplaces and progressive web apps. Unlike a website, a web app has user accounts, stores and processes data, and lets people complete tasks. It suits businesses replacing spreadsheets, manual processes or software that no longer fits.
Custom web app development services
Each is designed around how your users work and shipped as production software, with authentication, permissions and monitoring included.
Internal tools and back-office systems
Replacements for the shared spreadsheet, the email approval chain and the paper form: quoting tools, scheduling boards, inventory trackers and approval workflows, with an audit trail of who changed what.
Search, booking and reservation engines
Availability calendars, multi-filter search, pricing rules, deposits and confirmations, including the hard parts: double-booking prevention, time zones, currency conversion and calendar sync.
Progressive web app development
A progressive web app installs from the browser onto a phone's home screen, loads quickly, works offline for key screens and can send push notifications. One codebase serves desktop and mobile, with no app-store review. Since iOS 16.4, iPhones support web push for PWAs added to the home screen.
Real-time features
Live order feeds, chat, notifications, presence indicators and dashboards that update without a refresh. We use WebSockets, SignalR (for .NET backends), Supabase Realtime or Firebase, depending on the stack.
APIs and integrations
REST or GraphQL APIs, documented with OpenAPI, so your web app, mobile app and partners share the same data. We connect payment providers, CRMs, ERPs and shipping services, with webhooks keeping systems in sync.
Calculators, configurators and live lookups
Tools that turn visitor input into an answer, such as a quote, a recommended product or a location-based result, often using live external data.
Authentication, roles and security
Email and social login, single sign-on, multi-factor authentication and role-based access control so each user sees only what they should. We follow OWASP guidance, keep secrets out of the browser and validate every request on the server.
AI features
Search that understands plain-language questions, document summarization or an assistant inside your app, using OpenAI, Claude or Gemini models. See our AI integration services.
Web app, PWA or native mobile app?
| Web app | Progressive web app | Native mobile app | |
|---|---|---|---|
| How users get it | Visit a URL | Visit a URL, then install to home screen | Download from App Store or Google Play |
| Offline use | Limited | Key screens via service workers | Full |
| Device features | Basic (camera, location with permission) | Basic, plus push notifications | Full (Bluetooth, NFC, background tasks, health data) |
| Release updates | Instant | Instant | Through app-store review |
| Best for | Portals, tools, dashboards | Repeat-use apps on phones without app-store overhead | Heavy device use, offline-first, app-store presence |
Need deep device access or an app-store listing? See mobile app development; a shared API lets both run on one backend.
When your business needs a web app
- A core process runs on spreadsheets that get emailed around and overwritten.
- Customers phone or email for information they could look up themselves.
- You pay for three or four tools held together with Zapier, and something breaks every month.
- Off-the-shelf software forces you to change how you work.
- Partners, suppliers or franchisees need controlled access to your data.
- Your website needs to do real work, such as instant quotes, bookings or account management.
Selling the app to other businesses on subscription? That's a SaaS product, with multi-tenancy and billing on top. See SaaS development.
Why work with our web app development company
We question features before we build them
Every feature costs money to build and maintain. We map your workflow first and suggest what to cut, so version one ships sooner.
Full stack, one team
React, Next.js, Angular or Vue.js on the front end; Node.js, .NET / C# or Python and Django behind it. One team owns the whole app, so nothing falls between contractors.
Security written into the spec
Permissions, input validation and data access rules are specified and tested like any other feature, not patched in before launch.
Built to be handed over
Version control, automated tests on critical flows, deployment pipelines and documentation come standard, so your own team can take over.
Predictable communication
Email replies within 2–4 business hours, a staging demo every development cycle and an NDA on request. 2,000+ projects since 2014 have taught us that regular demos prevent surprises.
Our web application development process
- 01
Workflow mapping
We map the current process, user roles and data with the people who will use the app. Output: user stories and a first data model.
- 02
Clickable prototype
A Figma prototype of the main flows, tested with real users before any code is written.
- 03
Architecture and estimate
Stack, hosting, data model, integrations and security approach, with a fixed price or milestone-based estimate.
- 04
Build in short cycles
Each ends with a working demo on staging, and you can reprioritize between cycles.
- 05
Testing and acceptance
Automated tests for critical paths, permission checks for every role, load testing where traffic demands it, and user acceptance testing with your team.
- 06
Launch and iterate
Automated deployment, error monitoring and usage analytics. After launch, a retainer covers fixes and new features.
Tools & technologies
backend
- Node.js
- Express.js
- .NET / C#
- Python
- Django
data
- PostgreSQL
- MySQL
- MongoDB
- Redis
- Supabase
- Firebase
real time
- WebSockets
- SignalR
- Supabase Realtime
infrastructure
- AWS
- Microsoft Azure
- Google Cloud Platform
- Docker
- Vercel
common integrations
- Stripe
- CRMs
- ERPs
- calendar and channel-manager APIs
- OpenAI
- Claude
Work
Recent web app work
- wixengine.com/projects/the-house-keeowner portal and membership marketplace
The House Kee
A logged-in web app for property owners at a vacation-rental company in Maryland, Delaware and Florida: owner sign-up, login, paid membership plans and the Commissioning Week membership marketplace. We built the whole platform, from the guest-facing site to the owner portal.
Read The House Kee case study 
live postal-code lookup and configuratorsPurely Solutions
An e-commerce site for a Canadian water-filtration brand with interactive product configurators, financing at checkout and a live water-quality lookup by postal code.
Read the Purely Solutions case study
Cab booking platform — upgrade of an inherited system We took over a ride-booking platform from another developer and upgraded its booking system. Riders now see their trip on a live, interactive Google Map and can add extra stops along the way when they book.
What clients said
- Booking platform upgrade
“Five stars are not enough! Sohaib did an incredible job taking the Hash Cab platform to the next level. He took over a complex website and codebase built by someone else and understood it within days. He upgraded our booking system, added a live interactive Google Map, additional trip stops…”
ssamuelteferiUnited States · via Fiverr - Custom solution
“Working with Sohaib was an excellent experience from start to finish. He understood the project perfectly, communicated clearly, and implemented a technically clean and elegant solution that fits exactly what I needed.”
fflowerstarAustria · via Fiverr
How much does web application development cost?
Web application development with us starts from $3,000. A single-purpose tool with one or two user roles sits near that figure; apps with several roles, real-time features and multiple integrations cost more.
Running costs such as hosting, email delivery and paid APIs are estimated in the proposal.
You can work with us on a fixed price, a monthly retainer for continuous development, or hourly at $45/hour (minimum 40-hour block). Want a developer inside your team instead? See hire a React developer. Send your requirements and you'll have an exact estimate within 48 hours.
- User roles every role (customer, staff, manager, admin) means separate screens, permissions and tests.
- Workflows the number of distinct processes the app handles, from sign-up to refund.
- Integrations each connected system, especially older ones with weak documentation.
- Real-time and offline needs live updates and PWA offline support add architecture work.
- Data migration importing and cleaning records from spreadsheets or a legacy system.
FAQ
Frequently asked questions
How much does web application development cost?
Web application development with Wix Engine starts from $3,000 for a focused tool with one or two user roles. Costs rise with each additional role, workflow, integration and real-time feature. After a free call, we send a proposal within 24 hours and an exact estimate within 48 hours.
What's the difference between a website and a web application?
A website mainly presents information to visitors, while a web application lets users sign in and do something: book, order, track, upload or manage data. Websites are measured by traffic and leads; web apps by tasks completed. Many businesses need both, often sharing a design system and backend.
How long does it take to build a web app?
A focused web app MVP usually takes 6–12 weeks; larger platforms take several months and ship in phases. The biggest factors are the number of user roles, workflows and integrations. We break the work into milestones, each ending with a working demo.
Should I build a progressive web app or a native mobile app?
Build a progressive web app if your users need fast, repeat access on phones and you want one codebase without app-store reviews. Choose a native app if you need Bluetooth, NFC, background processing or an App Store presence. Many businesses launch a PWA first and add native apps once demand is proven.
Can you add a web app to my existing website?
Yes. A web app can live on a subdomain like app.yourcompany.com, share your website's login, or embed specific tools such as a quote calculator into existing pages. If your site runs on Wix, some features can be built directly with Wix Velo instead of a separate app.
Which technologies do you use to build web apps?
We usually build front ends in React or Next.js with TypeScript, and backends in Node.js, .NET / C# or Python with Django. PostgreSQL is a frequent database choice, with Redis for caching and Supabase or Firebase for faster MVPs. We choose the stack in the proposal based on your requirements and your team.
How do you keep a web app secure?
Security is part of the specification, not a final step. We use proven authentication, role-based permissions checked on the server, input validation, encrypted secrets and dependency updates, following OWASP guidance. Before launch, we test every role against data it shouldn't be able to see.
What happens after my web app launches?
We monitor errors and performance, fix launch issues free for the first 30 days, and hand over documentation and repository access. From there, you can keep us on a monthly retainer for improvements and new features, or take the app in-house. Either way, the code and infrastructure accounts belong to you once the project is paid in full.
Map out your web app with a developer
Book a free 30-minute call and walk us through the process you want to replace. We'll sketch the first version with you on the call and send a detailed proposal within 24 hours.
Sohaib Mehmood
Owner & CEO
Wix Legend Partner · 2,000+ projects since 2014 · 1,400+ client reviews