How much does website or app development cost?

Landing pages and small sites typically land at €50–100. Company sites and online stores at €200–500. Web apps, SaaS and mobile products at €200–500 depending on scope. You get a fixed price for a fixed scope before work starts, and any scope change is re-quoted in writing first.

How long does it take to build a website or app?

Landing pages take 3–7 days. Sites and online stores run 2–4 weeks. Web apps and mobile products take 6–12 weeks and are delivered in working stages rather than one drop at the end. The delivery date is confirmed in writing with the quote.

What if the product doesn't work as agreed?

Payment is split into stages and each stage is approved before the next is invoiced. Every project starts with defined, testable acceptance criteria, and a stage that does not meet them is fixed before work moves forward.

Web & App Development — Websites, Web Apps and AI Products

Capability index

Web & app development: what I can actually build for you

Not a list of tools I've heard of — these are the categories I take on end to end, from the first call through to a product running live with documentation attached.

Websites & landing pagesYour public face

Marketing sites, landing pages, portfolios and multi-page company sites — designed from scratch rather than dropped into a template. Fast on mobile, editable by you afterwards through a simple admin, and built so search engines can actually read them.

ResponsiveCMSSEO-readyMulti-language

Web applications & SaaSProducts, not pages

Full products with accounts, roles, permissions, billing and a database behind them. Booking systems, marketplaces, client portals, subscription platforms. I take an idea to a working MVP real users can pay for, then extend it as you learn what they actually need.

React / Next.jsAuth & rolesStripe billingMulti-tenant

Online storesE-commerce

Storefronts on Shopify and WooCommerce, or fully custom when the product doesn't fit a standard cart. Payments, delivery calculation, stock sync with your supplier, and the checkout tuned so people finish it.

ShopifyWooCommerceCustom checkoutStock sync

Mobile appsiOS and Android

Cross-platform apps from one codebase, so you're not paying twice for the same product. Offline mode, push notifications, in-app purchases, and I handle the part most people underestimate — getting it through App Store and Google Play review.

React NativePushOfflineStore publishing

Internal tools & dashboardsWhat your team uses daily

Admin panels, CRM systems, reporting dashboards, inventory and order management. Usually replacing a spreadsheet that four people edit at once. Built around how your team actually works, with permissions so the right people see the right things.

Admin panelsReportingAccess controlData import

Backend, APIs & databasesThe part nobody sees

Server logic, database design, REST and GraphQL APIs, background jobs, file storage, deployment and backups. Structured so the product still works when traffic grows and so the next developer can read it — that's a design decision, not an accident.

Node / PythonPostgreSQLREST / GraphQLCI/CD

Integrations & paymentsConnecting the rest

Payment providers, CRM, accounting, delivery services, calendars, email and messaging. Two-way sync and webhooks, plus custom API work when a ready-made connector doesn't exist for the system you already run.

StripeCRM syncWebhooksOAuth

AI features inside your productWhere it earns its place

Search that understands a question, an assistant answering from your own documents, recommendations, automatic tagging, generated descriptions. Added where it measurably improves the product — and left out where it's decoration. I'll tell you honestly which one you're asking for.

Smart searchAssistantsRecommendationsContent generation

Automation & workflowsAlso available

If part of your process still runs on copy-paste between tools, that can be automated too — intake, routing, notifications, scheduled reports and document processing. Usually built alongside a product rather than as the whole project, but I take standalone automation work as well.

n8n / MakeScheduled jobsDocument processingNotifications

Rescue, redesign & supportFixing what exists

A half-finished build, an agency that stopped replying, a site that's slow or broken on phones. I audit what's there and tell you plainly what's salvageable, quoting repair and rebuild as separate paths. Sometimes rebuilding is cheaper — you'll hear that from me if it's true.

Code auditPerformanceRedesignMaintenance

Before you ask

The things clients actually want to know

Answered here rather than after three emails, because these are the questions that decide whether it's worth having a call at all.

How much does custom AI development cost?

Landing pages and small marketing sites typically land at €100–200. Multi-page sites with a CMS at €200–500. Web apps, stores and mobile apps at 200–500 depending on scope.

You get a fixed price for a fixed scope before work starts. If scope changes mid-project, it's re-quoted in writing first — no invoice ever grows quietly.

How long does an AI project take to build?

Landing page: 1–3 days. Multi-page site with a CMS: 1–3 weeks. Web app or mobile app: 3–10 weeks, delivered in working stages rather than one drop at the end.

You get the delivery date in writing with the quote, and a status update every week whether or not there's good news.

Who owns the code and accounts afterwards?

You do — completely. Source code, repositories, hosting, domains, app store accounts, design files. Everything is registered in your name or transferred to you at handover.

Nothing runs on infrastructure I control, so I can't hold anything hostage and you can hire anyone else to continue. That's the point.

Is it GDPR compliant, and is my data confidential?

NDA signed before you send anything sensitive, no questions asked. A Data Processing Agreement before any build touches real customer data, and GDPR-compliant handling of user data by default.

Hosting can be kept inside the EU, and where an AI feature is involved I can build it self-hosted so nothing is sent to a third-party API at all. Your project isn't used in a portfolio or case study without written permission.

What if the AI system doesn't work as agreed?

Payment is split into stages — you approve the work at each one before the next is invoiced. If a stage doesn't meet what was agreed, it's fixed before anything moves forward.

Every project starts with defined acceptance criteria: specific, testable statements of what "done" means. Vague scope is how projects fail, so we pin it down before I write anything.

Is support included after launch?

90 days of support included on every build: fixes, tuning and questions answered, at no extra cost.

After that, an optional maintenance arrangement from €100/month covering updates, backups and small changes — or nothing at all. The project is documented well enough for your own team or another developer to take over. You're not required to keep me.

Do I need technical knowledge to commission a project?

No. You describe the problem in your own words — what happens now, what should happen instead, what it's costing you. Translating that into technical requirements is my job, not yours.

You'll never be sent a document full of jargon and asked to approve it. If something is explained in a way you can't repeat to a colleague, that's a failure on my side.

How do we communicate during the project?

Telegram or email, whichever you prefer. Replies within 24 hours on working days, usually much faster. Calls when a call is genuinely quicker than writing.

Working across EU and US time zones — send a message whenever suits you, and you'll have an answer by your morning.

What kinds of projects do you not take on?

Anything requiring a large team on a fixed enterprise timeline — I am one person, and pretending otherwise would cost you more than a straight answer.

Projects where the goal is unclear and won't be defined get declined too. If your idea isn't a fit, I'll tell you on the first message rather than take a deposit and find out later.

Process

How a project runs: four steps

The order matters here — each stage exists to remove a specific way projects go wrong.

You write to me

Telegram or the form below. Describe the problem in plain language — no specification needed. Rough ideas are fine; that's what the next step is for.

24h reply

We scope it properly

A short call or a written exchange to pin down what the product must do, what counts as finished, and what it will cost to run each month. You get a fixed quote, a delivery date and acceptance criteria in writing.

1–3 days

I build it in stages

Working pieces delivered as they're ready, not one reveal at the end. You approve each stage before the next is invoiced, so problems surface early while they're still cheap to fix.

3 days – 10 wks

Handover and support

Deployed live on your hosting, under your accounts, with documentation and a walkthrough for whoever will run it. 90 days of included support follow.

90 days included

Also available — courses

Or learn to build it yourself

I teach the same work I do for clients, on Udemy. Not tool tours — the actual method: building a real interface, wiring up a backend and database, adding AI features that hold up in production, and shipping something to a live URL.

Project-based — every module ends with something you built, not a certificate
No coding background needed to start
Written feedback on what you submit
Lifetime access, updated as the tools change

View courses on Udemy →

Contact

Tell me what you want built

Telegram is fastest. The form works just as well if you'd rather write it out in one go — both reach me directly, and you'll get a real answer either way, including if the answer is that I'm not the right fit.

Fastest — Telegram @aisewonet → Typically answered within a few hours on working days.

Email aisewo.net@gmail.com Attach files, briefs or screenshots — whatever you already have.

Not sure it's a fit?

Send it anyway. If it's outside what I do, I'll say so in the first reply and point you somewhere better where I can. No pitch, no follow-up sequence.

You describe the idea. I build the product that ships.