Client portals
Clients see their files, status, invoices or orders in one place that belongs to you.
App and custom software
An app that does exactly what your business needs.
Client portal, booking system, internal tool or web app: when off the shelf software does not fit, we build it. In phases, with a fixed price per phase. Start with a free clickable prototype within 72 hours.
- Free clickable prototype
- Fixed price per phase
- You own the code
- Management and development included
- 72hto your clickable prototype
- 3phases: discover, build, manage
- 100%owner of your own code
- 1team for design, build and management
Off the shelf software never quite fits. Custom does not have to be scary.
You juggle three tools and a spreadsheet because nothing does exactly what you need. Custom software sounds expensive and risky. That is why we work in phases: first a free prototype, then a fixed price discovery phase, then the build. You always know where you stand.
It works best combined with business process automation and an AI chatbot for your website . All from one partner, with one point of contact.
Booking and planning systems
Appointments, reservations and rosters, connected to payments and calendars.
Internal tools
That one process currently living in Excel, turned into a clean app everyone understands.
Web apps and mobile apps
Works in the browser, on phone and on tablet. Installable as an app where it makes sense.
AI built in
Smart search, document processing, predictions: wherever it genuinely adds value.
You are the owner
The code is yours. No vendor lock in, no licence per user.
How app development works at OneStone
- 01
Prototype
Within 72 hours, a clickable prototype of the key screens. Free. So you see straight away whether we are on the same page.
- 02
Discover
A short, fixed price phase where we work out exactly what the app should do and what it costs.
- 03
Build
In two week sprints. Every sprint you see working functionality.
- 04
Manage
Hosting, monitoring, updates and development per month. Grows with your business.
What is included?
- Design and user testing
- Build in sprints with demos
- Integrations with your existing systems
- Security and GDPR
- Hosting and monitoring
- Development and support
What does app development cost?
Never one vague number for "an app". After the free prototype comes a fixed price discovery phase, then a fixed price per build phase and a monthly fee for management. You can stop after any phase.
Request your free prototypeGood to know.
How long does building an app take?
A client portal or booking system is usually live within six to ten weeks. Larger apps we build in phases, so you have something in use quickly.
Can I stop after a phase?
Yes. Every phase delivers something usable and you own everything that is built.
Do you work with no code tools?
Where that is the smartest choice, yes. For anything that needs to scale or integrate, we build proper software.
Request your free preview.
Tell us briefly what you are after. Within 72 hours your free preview is ready: a first version of your website, an audit or a prototype. You pay nothing, you commit to nothing, and you only decide once you have seen it.
- Completely free preview
- Online within 72 hours
- No obligations, nothing upfront
- You can always just call us
What happens next
- Within 12 hours we get in touch to pin down what you need.
- Within 72 hours your free preview is online. You pay nothing.
- You decide. Want to go ahead? We agree on a price. Not for you? We simply stop.
+31 6 83605382
Talk directly to the person building your site. No ticket queue, no account manager in the middle.
Great, we are on it.
You will hear from us within 12 hours. Talk soon.
