Delight users
Concept and design
From first sketches to captivating designs that delight every user. Wireframes, clickable prototypes and a design system that works for your brand from day one.
App Development · React Native · Cross-Platform · PWA
App development for iOS & Android – apps users love
We build iOS and Android apps with React Native from one codebase – including concept, UX design, backend and store launch, for companies across NRW and remotely.
In short
App development at nextlevels means iOS and Android apps built with React Native from one codebase, including concept, UX design, backend and store launch. A first production-ready MVP starts from around €6,000 and usually takes a few weeks to a few months. References include the Toggo app for Super RTL and the BVB Kids App for Borussia Dortmund.
App experience in numbers
- 500k+
- App downloads
- 10+
- Industries
- 13
- Years of experience
Brands that work with us
App Development Services
End-to-end app development is what nextlevels stands for, with all of its expertise. Together with you we shape your digital future.
Ship faster
React Native app development
One codebase for iOS and Android, native in look, feel and performance.
One codebase
Cross-platform development
With efficient cross-platform technology, you build once and impress everywhere.
Reach everywhere
Web app development / PWA
Installable, offline-capable apps that run in the browser, no store needed.
Scale securely
Backend development
Robust backend solutions built for performance and scalability.
More downloads
App Store Optimization (ASO)
More visibility and downloads in the App Store and Play Store.
We build apps people genuinely enjoy using every day.
App development in NRW: what matters
An app is only as good as its daily use. That is why successful app development starts not with code but with the user: which problem do we solve, and how does the solution really feel on iOS and Android? We build native and cross-platform apps that are fast, stable and intuitive.
From the first idea through UX concept and prototype to launch, store optimization and maintenance, we accompany the entire lifecycle. The result is not an app that gathers dust in the store, but a product your users enjoy opening. We work with companies across NRW – and remotely throughout Germany.
Looking for a partner on site? At the head office of our digital agency in Mönchengladbach and as an app agency in Düsseldorf we also support you in person across the Rhineland – from concept to store release.
User-centered UX
Clear flows and thoughtful interaction instead of feature overload decide retention and ratings.
Performance & stability
Fast launches, smooth animations and low battery drain: technical quality you can feel.
Platform strategy
Whether native or cross-platform, we pick the stack to fit your budget, audience and roadmap.
Care & evolution
Updates, monitoring and new features keep the app relevant well beyond launch.
Having an app built: process & costs
An app project with us follows fixed steps: we clarify goal, audience and core features, build a clickable prototype, develop in short iterations with regular test builds and handle the store release. For most apps we use React Native app development: one codebase for iOS and Android with native UI components. If the application should run in the browser without a store download, a web app or PWA is often the leaner route.
Costs depend mainly on the scope and depth of the features, interfaces to existing systems, the backend and requirements such as login, offline use or push notifications. When the scope is clearly described we work at a fixed price; with open requirements we bill by effort with fixed milestones. The project calculator estimates a first range for your project from your answers. Team, references and way of working of our React Native developers are on the React Native agency page.
Why native & cross-platform?
One codebase. Both stores. Uncompromising user experience.
- Cross-platform
- iOS and Android from one codebase
- Native in look & feel
- Performance without compromise
- Scalable backend
- Grows with your user numbers
- You keep sovereignty
- Code and store accounts belong to you
How we work
Partnership, not a black box
We build apps from the user backwards: clear discovery, iterative development and transparent communication. You're involved at every stage, not just at go-live.
Discovery & strategy
Goals, platforms (iOS, Android, web) and scope are defined up front. That's the basis for a solid quote.
Concept & UX
User flows, screens and interactions are designed and validated as a clickable prototype before the first line of code.
Development in sprints
We build iteratively and ship testable builds early via TestFlight and Play Console. You give feedback at every stage.
Store launch & quality
Testing, performance and app-store guidelines are part of the deal. The release is planned, not improvised.
Operation & evolution
After launch we stay on board: updates for new OS versions, monitoring and continuous development.
Apps that delight users
With us you're always one step ahead technologically and tap directly into our extensive app development expertise. We take a close look at your app idea, identify key success factors and create tailor-made applications. Your visions and goals are at the heart of our joint project work.
Expert knowledge in app technologies
React Native, native iOS and Android development: we pick the stack to fit your project, not our preference.
Comprehensive user experience know-how
Intuitive operation and seamless interactions decide ratings and how long users stay in the app.
Proven track record
Published apps in the App Store and Play Store, from MVP to mature platform.
Versatile team
Concept, design, development and backend come together in one team that works without interface friction.
Long-term partnerships
We stay after launch and keep evolving your app with maintenance and updates.
What will your software or app cost?
Answer a few questions about your project – the Project Calculator shows a first range for cost and duration and the biggest effort drivers.
Start the Project CalculatorRelated goal: Build a new product
App Development Data & Insights
All postsWhat does it cost to have an app developed?
A first production-ready app (MVP) with a clearly scoped feature set typically starts from around €6,000. More complex apps with a backend, user management and multiple integrations often land in the low to mid five-figure range. On top come running costs for operations, store fees and maintenance. You get a concrete offer after a discovery in which we sharpen the feature set and target audience.
What drives app development costs?
The biggest cost drivers are the feature set, the platforms (iOS, Android or both – cross-platform saves significantly here), backend requirements such as user accounts or sync, integrations with existing systems, and the level of ambition in design and animations. Offline capability, push notifications and multi-language support also play a role. In the discovery we prioritize together what belongs in the MVP and what can come later – the most effective lever for controlling cost.
How long does it take to develop an app?
An MVP usually takes from a few weeks to a few months. We recommend starting with a clearly focused feature set, releasing early and evolving based on real user data, rather than trying to build every feature from the start.
Native or cross-platform – what do you recommend?
For most projects cross-platform – with React Native in our case – is the most economical choice: one codebase for iOS and Android, faster development, lower maintenance. Native development is worth it for very hardware-close requirements or maximum performance demands. We decide based on your requirements, not on technical preference.
Do you develop for iOS, Android or both?
Both. As a rule we serve iOS and Android simultaneously from one cross-platform codebase. If your market clearly sits on one platform, it can make sense to start there and expand later – we'll discuss that honestly too.
Do you handle publishing to the App Store and Play Store?
Yes. We handle publishing to the Apple App Store and Google Play Store including the store listing, review process and the stores' technical requirements. The developer accounts run under your name, so you always keep sovereignty over your app.
What happens after launch – do you offer maintenance and updates?
An app is never 'finished'. Operating systems, devices and stores change constantly, and users expect ongoing improvement. We offer maintenance, monitoring and further development so your app stays compatible, secure and up to date – at the scope that fits your project.
Who owns the source code?
You do. Code, designs and accounts belong to you. We document the project so another team could take over. Vendor lock-in is not our business model but a risk we actively avoid.
How do you ensure quality and security?
Quality assurance and testing are an integral part of our process, not a step at the end. We test on real devices, pay attention to data protection and secure data transfer, and set up processes so bugs surface early. That way your app goes live stable and stays that way.
Do you also develop apps in Mönchengladbach and NRW?
Yes. nextlevels is based in Mönchengladbach and runs app projects in the region and across NRW – on site or remotely. The process from concept through iOS and Android development to store launch stays the same, whether you are in Mönchengladbach, Düsseldorf or Cologne.
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READY FOR YOUR APP THAT SETS NEW STANDARDS?
Whether you want to optimize an existing app or bring a new vision to life: we'd love to meet you. A no-obligation conversation is always a great start.
What's it about?
Paul Kalisch
Executive Partner
- 30 minutes by video or phone
- You talk directly to a partner, not to sales
- You get the order of steps, risks and rough costs
All app development services at a glance