Reporting eats the morning
Pulling numbers from three or four disconnected tools and reformatting them into something a client can read takes hours, every week, for every client.
Custom web app development services for client portals and data apps
My custom web app development services cover the logged-in tools B2B firms build around their own data: client portals, customer portals and internal apps. The most common one is a portal where each client finds their live dashboards, monthly reports and shared files behind one login, without you emailing a PDF every Monday. You tell me how your client relationships work and what each person should see, and I design the app around that.
Custom quote 4.9 from 80+ reviews on data and dashboard workClients in the US and Europe
A concept lead-generation report for a fictional agency on sample data, the kind of view one client would see after logging into their portal.
Sound familiar?
Clients keep asking for the latest numbers
Your team answers the same 'can you send me the current figures?' emails, and the answer is out of date the day after you send it.
Sharing reports outside the company is messy
Guest accounts, shared links and per-user licences make it hard to be sure each client sees only their own data.
What you get
A starting point, never a fixed package: describe how you want it and I build it to match.
One secure login per clientEach client user signs in and sees only their own company's data, enforced in the database with row-level security.
Live dashboards per clientThe KPIs that matter for your service, refreshed automatically from your sources and filtered to that client.
Your brand on itA white label client portal with your logo, colours and domain, so clients see your service and not a third-party tool.
An admin view for your teamAdd clients and users, switch between client views, and see every account in one place.
Files and reports in one placeMonthly packs, contracts and deliverables stored next to the dashboards instead of scattered across email threads.
An optional monthly AI noteA short written summary of what changed for each client, drafted by AI from the data and approved by your team before clients see it.
Custom web app development services or client portal software?
Off-the-shelf client portal software is a good choice when your needs are standard: file sharing, messages, invoices, e-signatures. Plenty of tools do that well, and I'll tell you if one of them fits better than a build. A custom client portal makes sense when the reason clients log in is your data: campaign results, project progress, stock levels, financial figures, anything that comes out of your own systems and needs calculating before a client can read it.
That is where portal tools tend to run out. They can host a PDF, but they can't join your CRM, your ad accounts and your time tracking into one per-client view, or apply your definition of a conversion. My custom web app development starts from the data model, because I've spent 5+ years as a Power BI data and business analyst. The screens are the easier part once the numbers underneath are right. The same approach works for internal tools development, where the users are your own staff instead of clients.
Customer portal development: who sees what
The worst thing a client or customer portal can do is show one account another account's numbers. I enforce access in the database itself, with row-level security, so a mistake in a screen can't leak data across accounts. Every user has their own login, your team gets an admin role, and access is removed in one place when someone leaves.
I'm based in the EU and work under GDPR, which also suits US firms with European clients. The database can sit in an EU region where the provider offers one, NDA and DPA are available on request, and you own the code, the database and the domain. If you already report in Power BI, embedding those reports is possible, but it brings its own licensing cost; a web dashboard inside the portal needs no per-user licence.
How it works
Map users and data
We list what each client or team should see, where that data lives today, and who needs access.
Data model and access rules
I connect the sources, build one clean data model and define exactly which rows each user may see.
Build and pilot
I build the app and run it with one friendly client or team first, then fix what they stumble over.
Roll out and hand over
Everyone gets access, your team learns the admin side, and you receive the code, repository and documentation.
Pricing
Custom quote
The fixed price depends on how many data sources feed the app, how many different client or user views you need, and extras such as file sharing or an automated monthly note.
- Every project is scoped with you, then priced as one fixed quote
- Built to your wishes: tell me exactly how you want it
- Optional care plan afterwards to keep it running
Work you can check
The client reviews on this site are about data and dashboard work. For this service, here is work you can open and judge yourself, each labelled for what it is.
A stock analysis platform I designed, built and run myself: the interface, the web app and the data pipelines behind it, with scheduled refreshes.
Visit Intrinsiqqflippielabs.com: designed, written and built by me, including the live example dashboards and the contact form backend.
See the examplesLive dashboards for fictional companies, built by me on sample data to show what a finished build looks and feels like.
Browse the examplesCustom web app development services: questions answered
Anything else? Ask me directly, I reply within a few hours on working days.
How much do custom web app development services cost?
My custom web app development services are quoted as a fixed project price once I have read your brief. For a client portal, the cost depends mainly on how many data sources feed it, how different the views are between clients, and extras such as file storage or an AI-written monthly note. Ongoing hosting and support can be covered by a monthly Care plan, with its terms agreed in writing before it starts.
Can you build it exactly the way we want?
Yes, and that's the main reason to build one instead of buying a tool. You describe how your client relationships work, what each client should see and what your team needs to manage, in your own words. I match that as closely as I can. If part of your wish list is cheaper to solve with an existing tool, I'll say so.
Can one client ever see another client's data?
Not if the portal is built properly, and I build it so they can't. Access rules live in the database through row-level security, so every query is filtered to the signed-in client before any data reaches the screen. A bug in a page can't override that. Admin access for your team is a separate role, and each client user has an individual login.
Can the portal be white label, under our own brand?
Yes. A white label client portal runs on your own domain or subdomain, with your logo, colours and email sender, so clients never see my name or a third-party product. Because it's custom built, there's no vendor branding to pay to remove. You own the code and the repository, so the brand stays yours if someone else maintains the portal later.
Do you also build internal tools, not just client portals?
Yes. Internal tools use the same building blocks as a client portal: logins, roles, a database and screens that read and change data. Typical examples are an approval flow that replaces an email chain, an admin panel for orders, or a planning view that replaces a shared spreadsheet. I scope them the same way, starting from the data and the people who use it every day.
Can the portal use our existing Power BI reports?
Yes, Power BI reports can be embedded in a portal, but embedding for external users needs its own Microsoft capacity licensing, which adds a recurring cost. The alternative is a web dashboard built inside the portal, which needs no per-user licence. I'm Microsoft-certified in Power BI, so I can compare both options against your client count before you decide.
Who owns and hosts the portal?
You own it. The code sits in a repository under your account, the database and hosting are in your name or transferred to you at handover, and the portal runs on your domain. Hosting is usually on Vercel and Supabase, with the database in an EU region where the provider offers one. Another developer can take it over later without starting from scratch.
Do you work with agencies and firms in the US?
Yes. Many of my clients are in the US and Canada, and I work in English and asynchronously from the Netherlands. I reply within a few hours on working days, so you can send questions at the end of your day and often have answers or progress by the next morning. I sign an NDA or a DPA on request before touching client data.
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