Web Applications
Off-the-shelf solutions eventually reach their limits. We develop web applications that do exactly what your company needs—and nothing it doesn’t.
Have Web Applications Developed
We develop custom web applications: from small tools to complex portals with user roles, databases, and API integrations. Each solution is tailored to your needs and built so that your team can use it independently and we can continue to develop it over the long term.
From the configurator
to the customer portal
Modern technologies,
maintainable code
A team for design,
development, and operations
Web applications that map your processes
Every company has workflows that no off-the-shelf tool can perfectly accommodate. Whether it’s managing customer inquiries, overseeing projects, analyzing data, or automating calculations—if your processes are too unique for standard software, we’ll build the solution for you. Our web development services range from simple form solutions and calculators to complex portals with user roles and database integration. Every application is designed to integrate seamlessly into your existing infrastructure. You won’t receive a solution that you have to adapt—instead, you’ll get an application that supports your business.
Design and Technology from a Single Source
A web application must not only work, but also be user-friendly. That’s why UX/UI design and development are handled by the same team at our company. The result: applications that are technically sound and intuitive to use. We design the user interface and build the underlying logic, from the prototype to the finished application. We want your users to enjoy using the application—not just be able to use it. This saves time on training and increases acceptance within the team. The design follows your corporate guidelines or is created from scratch if you need a fresh look.
Web applications come in many forms, ranging from simple online tools to comprehensive platforms with user roles and interfaces. The following project types provide an overview of the applications we develop most frequently.
Customer Portals
Areas for your customers: View projects, download documents, submit requests, or track the status of orders. Protected by login credentials and user roles, and integrated with your systems.
Dashboards and Reporting
Consolidate data from various sources and present it clearly: KPIs, analytics, and reports in real time. We build dashboards that provide your teams with the information they need to make decisions.
Configurators and Calculators
Product configurators, price calculators, or quote tools: interactive applications that take the work off your customers’ or sales team’s hands. Featuring dynamic calculations, PDF export, and optional CRM integration.
Internal Tools and Workflows
Task management, approval processes, or data collection: We build internal tools that your teams use every day. Tailored to your workflows, not to a software vendor’s vision.
Self-service platforms
Areas where your customers or partners can act independently: placing orders, updating data, and creating tickets. This takes the pressure off your team and gives your users control.
Interfaces and Integrations
Connecting existing systems: CRM, ERP, accounting, or external APIs. We build the interfaces that connect your web application to the rest of your IT landscape. They’re well-documented and easy to maintain.
These companies know how we work
A customer portal gives your customers direct access to information and features that would otherwise be handled via email or phone. We develop portals with login functionality, user roles, and customized views for each customer group. Typical features include: project overview, document storage, order history, and communication tools. The data is sourced from your existing systems via integrated interfaces. The portal runs as a web application and is accessible via any browser. E-commerce features, such as order placement and request for quotes, can also be integrated. We design the user interface so that your customers can navigate it without training. Every portal is developed to be responsive and works on desktops, tablets, and smartphones. We prioritize security and data protection from the very beginning. Anyone looking to have web applications developed usually starts right here.
„In addition to the entire team’s tremendous expertise, we especially appreciate how easy and quick it is to get in touch with them, even when things get urgent. Every problem, no matter how small, is taken seriously and resolved immediately.“
Julian Ellermann
arcus physio
„Since we started working with seitenweise, our website has improved significantly. In 2023, they used their extensive expertise to transform our static website into a dynamic WordPress site.“
Dirk Bockelmann
DFT
„The team at seitenweise consists of our graphic design and web development professionals. Whenever we need help, they’re always there for us—quickly and reliably. Thank you for the great collaboration!“
Sandra Meder
Sage
„Working with an agency requires good ideas, cutting-edge technology, and clear budgets with no surprises. But the personal chemistry has to be right, too. With seitenweise, everything was just right. It was really fun.“
Mathias Schwaben
Intervideo
„In addition to the entire team’s tremendous expertise, we especially appreciate how easy and quick it is to get in touch with them, even when things get urgent. Every problem, no matter how small, is taken seriously and resolved immediately.“
Julian Ellermann
arcus physio
„Since we started working with seitenweise, our website has improved significantly. In 2023, they used their extensive expertise to transform our static website into a dynamic WordPress site.“
Dirk Bockelmann
DFT
„The team at seitenweise consists of our graphic design and web development professionals. Whenever we need help, they’re always there for us—quickly and reliably. Thank you for the great collaboration!“
Sandra Meder
Sage
„Working with an agency requires good ideas, cutting-edge technology, and clear budgets with no surprises. But the personal chemistry has to be right, too. With seitenweise, everything was just right. It was really fun.“
Mathias Schwaben
Intervideo
Here's How Your Web Application Is Created
Requirements Analysis
Together, we clarify what the application is intended to do: What processes does it support? Who will use it? Which systems need to be integrated? In doing so, we distinguish between what is necessary from the start and what can be added later. We document these requirements as the foundation for the design and development. This way, we start with a shared understanding rather than assumptions.
Concept and Prototype
Based on the requirements, we develop a concept that includes wireframes and a clickable prototype. You’ll get an early sense of what the application looks and feels like. Feedback is incorporated directly into the next iteration. Your future users can also try out the prototype before a single line of code is written. The prototype saves time during development because misunderstandings are identified early on.
Development
Development proceeds in sprints: Every two weeks, we deliver a working interim version that you can test and provide feedback on. This keeps the project manageable and transparent. You can adjust priorities between sprints if requirements change. Every feature is documented and validated with automated tests. We follow best practices for code quality to ensure your application remains maintainable.
Testing and Launch
Before the launch, we test the application for functionality, security, and performance. Your users also test it in a staging environment. Their feedback is incorporated into the application before it goes live. The application goes live only once everything is running smoothly. The launch is supported and monitored. A contingency plan and rapid support channels ensure that we can respond to problems immediately.
Operation and Iteration
After launch, we monitor the application and respond to feedback. We continuously install updates and security patches to ensure the application remains stable. Monitoring continues and flags any anomalies before your users notice them. We implement new features and improvements in subsequent sprints. The application grows along with your requirements without compromising the existing architecture.
Frequently
Asked
Questions
Custom
Maintainable
We build applications that map your processes.
seitenweise is a digital agency based in Bielefeld, founded in 1999. With over 500 projects and more than 100 clients, we combine custom software development with design, strategy, and long-term support. For us, web applications aren’t a byproduct—they’re a core competency. The team that designs and develops your application also supports it after launch. We work primarily with medium-sized businesses in the East Westphalia-Lippe region and throughout Germany that want to digitize their processes. Short communication channels, direct contact, and a team that knows your project inside and out.
Marcel and André are your points of contact at seitenweise. They’ll be happy to answer any questions you have about web applications.
Your process deserves a custom solution. We'll build a web application that does exactly what your business needs and continue to develop it together with you.