I'm Jim Clermonts, a freelance App developer based in Amsterdam with 10+ years of experience building native apps for enterprise clients. From concept to launch — I deliver apps that perform.
Building a successful mobile app requires more than just writing code. It demands deep platform expertise, an understanding of user behavior, and the ability to architect solutions that scale with your business. As a dedicated Android developer with over a decade of experience, I bring all three to every project I take on.
I've built apps for the Netherlands' largest charity lottery (600,000+ users), banking institutions with strict regulatory compliance, payment terminals processing thousands of transactions at live events, and luxury retail brands where every pixel matters. Each of these projects demanded a different approach, but they all share the same foundation: clean architecture, thorough testing, and a relentless focus on the end user.
Unlike agencies where your project gets passed between account managers and junior developers, when you work with me, you work directly with the person building your app. This means faster communication, fewer misunderstandings, and a developer who truly understands your product vision.
My core competence is native Android development. However, I can also deliver the complete project for iOS, Android and back-end. For this I leverage my network of worldclass developers. I then take on the role as project manager.
Building your app from scratch with a modern, scalable architecture. From initial requirements to Play Store launch, I handle the complete development lifecycle using Kotlin, Jetpack Compose, and modern architectural patterns.
Migrating legacy Java apps to Kotlin, adopting Jetpack Compose, implementing modern architecture patterns, and updating dependencies. I bring your existing app up to current Android standards without disrupting your users.
Architecture reviews, code audits, and technical guidance for your Android team. I help teams identify bottlenecks, improve their codebase, and adopt best practices that reduce bugs and speed up development.
Beyond development, I offer product ownership services — managing backlogs, aligning stakeholders, writing user stories, and ensuring your app delivers maximum business value with every release.
I work exclusively with the native Android ecosystem, ensuring maximum performance, full access to platform APIs, and the best possible user experience. My technology stack includes:
Tell me about your project and I'll provide an honest assessment of the approach, timeline, and investment needed. No obligations, no sales pitch — just a straightforward conversation between professionals.
