What is a custom web application?
Software accessed through a browser, designed precisely around your business processes. It needs no installation and works on a computer, tablet and phone.
At first glance a web application looks like a website, but its job is not to inform, it is to work with data. Users log in, enter information, see overviews and the application carries out tasks for them. If you are looking for someone to build one for you, have a look at my services.
"Custom" means the application is not a boxed product. It contains exactly the features you need, with an interface adapted to your people.
What is the difference between a website and a web application?
A website presents a business and informs. A web application is for work: it has users, data and features that handle a specific process.
Website
- presents the business, services and contact details,
- the content is the same for every visitor,
- the goal is to earn trust and enquiries.
Web application
- users log in and each sees their own data,
- it contains forms, overviews, filters and exports,
- the goal is to make work simpler and faster.
In practice they are often combined. A business website can have, for example, a client area or online ordering, which are really a small web application. What the website itself should contain is covered in the article on recognising a quality business website.
How do a website, a spreadsheet and a web application differ?
A website informs visitors, a shared spreadsheet is a quick tool for a small team, and a web application adds users, permissions, checks and automatic steps.
Many businesses start with shared spreadsheets, and that is sensible. The table below shows where the limits of each solution lie and when it is worth considering the next step.
| Feature | Website | Shared spreadsheet | Web application |
|---|---|---|---|
| Main purpose | presentation and winning enquiries | record keeping and simple calculations | working with data according to a process |
| Users | anonymous visitors | anyone with the link or access | logged-in users with roles |
| Data checks | not needed | limited, data is easily overwritten | checks on entry, change history |
| Automation | forms and notifications | formulas, possibly scripts | rules, notifications, integrations |
| When it stops being enough | when you need to work with data | when spreadsheets multiply and overwrite each other | when the process changes, the application is extended |
This does not mean spreadsheets should be thrown away. Often the best first step is an application that replaces only the part where errors occur and leaves the rest as it is.
When does a business need a custom web application?
When off-the-shelf software does not handle your process, when data lives in several spreadsheets and emails, or when you want to offer customers your own online service.
Typical signs that it is time for your own application:
- the team works in dozens of shared spreadsheets that overwrite each other,
- the same data is retyped by hand into several systems,
- off-the-shelf software forces you to adapt your process to it, not the other way round,
- you pay for several tools and use each of them only partly,
- you want to offer customers bookings, a client area or a calculator that competitors do not have.
Examples of applications I have built
- Patient booking for Gynkomed: distinguishes registered and new patients, services have their own length and the clinic sees a weekly schedule in 15-minute slots. More in the article on a booking system.
- An online shop with admin panel and CRM for JF MOTO: the motorcycle dealer has products, orders and customers in one system.
- Job management for KRYŠTOV Group: a window manufacturer in Brno manages its jobs through its own admin panel.
- An ROI calculator for M2M Solutions: calculates the savings and payback of a logistics system and stores the contacts of interested visitors. More in the article on configurators and calculators.
- Marxyo: my own SaaS, a digital reception for clinics with announcements, e-prescription requests, reminders and bookings.
How is a custom web application developed?
Development runs in six steps: analysis, interface design, development in parts, testing, launch and further development.
- Analysis: understanding the process, the users and what the application should solve.
- Design: sketches of screens and flows, so you can see how the application will be used before programming starts.
- Development in parts: the most important features first, so they can be tried out early.
- Testing: with real users and real data.
- Launch: data migration, training and deployment to the server.
- Further development: more features are added based on feedback.
I almost always recommend a first usable version with the most important features (an MVP) instead of designing everything at once. You quickly find out what users really need.
Which technologies are used to build web applications?
An application has a browser interface, a server side with the logic and a database. I build on JavaScript, Node.js or PHP and a PostgreSQL database, most often via Supabase.
- Frontend: what the user sees and works with in the browser.
- Backend: the application logic, permissions and connections to other systems.
- Database: secure data storage with backups.
- Integrations: connections to email, invoicing, a payment gateway, CRM or AI.
These are widely used technologies without licence fees, so another developer can take the application over later. Artificial intelligence is an increasingly common part of applications too, for example AI automation that processes data in the background.
When to choose off-the-shelf software and when your own application?
Off-the-shelf software is a quick start for standard processes. Your own application pays off when the process is your competitive advantage or when off-the-shelf tools constantly have to be worked around.
Off-the-shelf tools are good today and are perfectly sufficient for many businesses: there is no need to develop anything of your own for accounting, email or document sharing. The situation changes when a business does something differently from others and that very difference is why customers choose it.
Off-the-shelf software suits you when
- the process is standard and thousands of businesses do it in a similar way,
- you need a solution immediately,
- the features the tool offers are enough for you.
Your own application suits you when
- the process is specific and gives you an advantage,
- you combine several tools and copy data between them by hand,
- you want full control over your data and further development,
- you plan to grow and need a solution that grows with you.
A combined solution is also common. Off-the-shelf tools stay for what they are good at, and a small custom application connects them and fills in the missing part. This approach is often faster and more economical than building everything from scratch.
What to prepare before the first meeting
- A description of the process you want to simplify, including who is involved.
- Examples of the spreadsheets, forms or documents you work with today.
- A list of tools you already use and that should stay.
- An idea of what should improve once the application is launched.
What does a web application bring a business?
One place for data, less manual retyping, a real-time overview and a process that works the same regardless of who is on shift.
The biggest change after launching an application is usually visibility. Instead of asking "where is that spreadsheet" and "who is responsible for this", everyone sees their own tasks and management sees the overall status. A new colleague learns faster because the application guides them through the process step by step.
The second benefit is reliability. Data is entered once, checked on entry and backed up automatically. Retyping errors disappear and the business can make decisions based on current figures rather than estimates. The application also creates a foundation to which AI features and further automation can be connected later.
How is a web application secured?
Security rests on an encrypted connection, login with roles, server-side input validation, regular backups and updates. These points are worth asking about before development starts.
A web application works with business data and often personal data, so security is part of the design from the start, not an add-on at the end:
- HTTPS: all communication between the browser and the server is encrypted.
- Login and roles: each user sees and changes only what they are authorised to.
- Server-side validation: data is checked on the server, not only in the browser.
- Backups: regular and verified, with the option to restore.
- Updates: the libraries used and the server are kept up to date.
- Logs: for sensitive operations it is useful to know who changed what and when.
What should you consider when choosing a web application developer?
Check their experience with similar projects, agree on ownership of the code and data, and on how support and further development will work.
- Ask about similar projects and their way of working.
- Agree on who owns the source code and the data.
- Make sure the application will have backups and security.
- Agree on the form of support after launch.
- Prefer gradual development with regular demos over one big handover.
Frequently asked questions
What is a custom web application?
Software accessed through a web browser, designed precisely around a business's processes. Users log in, work with data and the application carries out repetitive tasks for them.
What is the difference between a website and a web application?
A website presents a business and informs visitors. A web application is for working with data: it has login, users and features that handle a specific process.
How long does it take to develop a web application?
It depends on the scope. A smaller tool, such as a calculator, takes days to weeks. I build a larger system in parts so that the first usable version is available as soon as possible and further features are added gradually.
How much does a custom web application cost?
The price depends on the number of features, users, connections to other systems and security requirements. I will prepare a proposed solution and a price estimate free of charge within 2 working days.
Does a web application work on mobile?
Yes. A web application runs in the browser, so it works on a computer, tablet and phone without installation. I design the interface so that it is comfortable to use on all devices.
Free proposal within 2 working days
Write me a few sentences about what you need. I will get back to you within 24 hours. An overview of everything I do is on the services page.
Contact meI build custom websites, web applications and AI solutions for businesses in Slovakia, the Czech Republic and beyond. I write about how technology can save small businesses time and bring new customers.
