Services / Custom web app development
Custom web app development for small businesses
When an off-the-shelf plugin doesn’t fit, we build the tool your business actually needs: a client portal, a booking or quoting system, a members area, a calculator, or an internal dashboard. Scoped in plain language, priced before we start.
Typical investment
Quoted per project
Small tools start around $2,500. Portals, booking systems and cloud applications typically run from $7,500 to $30,000 and up, depending on complexity. Everything is fixed-price once scoped.
Fixed price and timeline before development begins.
Who our custom web app service is for
You run your business on spreadsheets and email and something keeps falling through the cracks.
Your customers keep asking for the same thing — a quote, a booking, a document — and you answer each one by hand.
You’ve outgrown the plugins and stacking three of them together has become fragile.
What’s included in our custom web app service
- Plain-language scoping session and written spec
- Fixed price and timeline before development begins
- Built on WordPress where it makes sense, standalone when it doesn’t
- Integrations with payments, calendars, email, CRM and accounting tools
- User roles and permissions done properly
- Secure, tested and backed up from day one
- Documentation and handover so you are never locked in
- Training for your team
- Ongoing support available under your maintenance plan
The tools we build with
We pick the stack that fits the job rather than forcing every project through the same one. Everything we build uses current, well-supported technology, so another developer could pick it up years from now.
Frontend
- React and Next.js for fast, app-like interfaces
- Vue and Nuxt where a lighter build fits better
- TypeScript throughout, so bugs surface before launch
- Tailwind CSS for interfaces that stay consistent as they grow
- Responsive and accessible by default, tested on real devices
Backend
- Node.js and Python for APIs and business logic
- PHP and Laravel when the project lives close to WordPress
- PostgreSQL and MySQL for structured data, Redis for speed
- REST and GraphQL APIs, documented so anyone can use them
- Background jobs and scheduled tasks for work that runs on its own
Integrations
- Payments: Stripe, PayPal
- Calendars and scheduling: Google Calendar, Outlook, Calendly
- CRM and email: HubSpot, Mailchimp, Brevo, Resend
- Accounting and operations: QuickBooks, Xero, Zapier, Make
- AI: OpenAI, Anthropic and other providers, where it genuinely helps
- Your existing WordPress site, so everything works as one product
Hosting and delivery
- Cloud hosting on AWS, DigitalOcean or Vercel, sized to the project
- Docker and Git-based deployment, so releases are repeatable
- Automated backups, monitoring and error alerts from day one
- SSL, role-based access and security reviewed before launch
- Documentation and handover, because you own what we build
Not sure which of these you need? That’s our job. Tell us what the tool has to do and we’ll recommend the simplest thing that will still be standing in five years.
How our web app development process works
No jargon, no surprises. You will always know what happens next and what it costs.
1
Scoping
We map out what the tool needs to do, step by step, in your words. You get a written spec and a fixed quote.
2
Prototype
You click through a working prototype before we build the real thing, so surprises happen early and cheaply.
3
Build and test
We build in stages, show you progress every week, and test with real data.
4
Launch and support
We launch, train your team, and stay available for improvements as your business changes.
Recent custom web apps we designed and built
Technology / SOPs
Systems Success Pro
A custom web application built alongside the WordPress site, hosted and maintained by us.
Custom web app · Hosting
Religion
Archdiocese of Miami
Custom development for a large organisation with complex requirements.
Custom development
Reviews from small businesses in Miami, Florida and beyond
Custom web app questions, answered
Client portals, booking and scheduling systems, quote and estimate generators, members-only areas, price calculators, order forms, small internal dashboards and integrations between tools you already use.
Small tools start around $2,500. Portals, booking systems and cloud applications typically run from $7,500 to $30,000 and up, depending on complexity. Everything is fixed-price once scoped.
No. That is what the scoping session is for. Describe the problem and we design the tool together.
Yes. Most of what we build lives inside your WordPress site or connects to it, so it looks and feels like part of your brand.
You do. Everything is documented and handed over.
Custom web app development in Miami, Fort Myers, Austin and nationwide
Klashtech is headquartered in Miami, Florida, with clients in Fort Myers and Southwest Florida, Austin, Texas, and across the United States. Most work happens over video, so location never limits who we can help. We work in English and French, which makes us a natural fit for French-speaking entrepreneurs building a business in the US.
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