App development for web, iOS and Android that lasts for years
Applications that hold up in your users' daily work
Customer portal, line-of-business application or mobile app: we build applications for web, iOS and Android that keep running after launch. We focus on what software has to withstand in operation: real users, growing data volumes, new requirements.
Our core is the TypeScript ecosystem with React, Next.js and Expo. We are at home there, but not dogmatic about it: when a project calls for Swift, Kotlin or .NET, we build with those.
Design and engineering sit at the same table. That is why we produce interfaces that can actually be built, and code that actually delivers the designed experience.
The typical situation
People taking a training course expect digital support before, during and after the session, even without a laptop. For a digital wealth manager, the web application is the product: any friction in the interface is friction in the core business.
How we approach it
- Web and mobile as one product: For Haufe Akademie we built an iOS app with React and Expo and extended the existing Next.js platform. Components from the app flowed back into the web.
- A design lead in the engineering team, so web and app speak the same visual language.
- One brand across all channels: For Buchinger Wilhelmi, the app and the web ordering flows share the same brand identity and tone.
- Embedded, ongoing development: At quirion we worked on the platform as the frontend and UI team inside the client's engineering organization.
We worked on web and app for Haufe Akademie for more than 12 months, and on quirion's React frontend for 2 years.
How it works
We build applications in three phases. Each phase ends with a result you use to decide whether and how to continue.
- Consulting and architecture, from one week: We work out which platforms you need, whether web and mobile share one codebase and how the application connects to your systems. The result is a decision paper with architecture, options and an effort estimate.
- Prototyping and pre-study, typically 2–6 weeks: We test interfaces and flows early with a clickable prototype, before any production code is written. The result is a clickable prototype, a risk assessment and a solid implementation plan.
- Engineering and operations, months to years: We build the application, either as a project under our responsibility or embedded in your team, and keep developing it in operation. The result is software in production, documented and ready to hand over to your team.
We worked on web and app for Haufe Akademie for more than 12 months, and on quirion's React frontend for 2 years. You can find an overview of the phases under Services.
Technologies
Our core is the TypeScript ecosystem. These are the technologies we use in app projects:
- Web: React, Next.js and TypeScript, with Styled Components at Haufe Akademie
- Mobile: Expo and React Native, shipped for iOS and Android
- Native when the project calls for it: Swift, Kotlin or .NET
- Design: Figma, with a design lead in the engineering team
- Testing: Jest, Cypress and Playwright
We decide which combination fits during the consulting phase, based on your requirements and your team.
Frequently asked questions
Do you build apps natively or cross-platform?
Mostly cross-platform. Our core is the TypeScript ecosystem with React, Next.js and Expo, which lets web and mobile grow from a shared base. For Haufe Akademie we built the iOS app with React and Expo. Components from the app later flowed back into the web platform. When a project calls for Swift, Kotlin or .NET, we build with those. The decision is made in the consulting phase.
Can you continue developing an existing application?
Yes. At quirion we spent two years as the frontend and UI team inside the client's engineering organization, building on the existing React platform. At ImmobilienScout24 we work in a codebase that has grown over many years: we add TypeScript types, draw clearer component boundaries and remove legacy patterns. We work as part of your team, not as an outside vendor.
How do you keep web and app consistent in design?
Design and engineering sit at the same table. For Haufe Akademie, a design lead was part of the engineering team so web and app speak the same visual language. For Buchinger Wilhelmi, the app and the web ordering flows share the same brand identity and tone. The result is interfaces that can actually be built.
How long does an app project take?
That depends on the scope. Consulting starts at one week. A pre-study with a clickable prototype typically takes two to six weeks. Build and operations run for months to years. We worked on web and app for Haufe Akademie for more than 12 months, and on quirion's React frontend for 2 years. After each phase you decide whether and how to continue.
- Web applications with React and Next.js
- Mobile apps with Expo and React Native
- Customer portals and self-service flows
- Line-of-business applications for daily operations
- Accessibility under the EAA and WCAG
- Performance and maintainability
- Products that keep running after handover
- One codebase for web and mobile
- Fast iteration without losing quality
- Users who like coming back
- Short paths between design and code