Mobile Developer

Mobile Developer (Freelance) - 3 Months - Brussels Belgium

At RELYzIT Talent, we don’t recruit — we build. We unite the top 2% of builders — engineers, architects, creators — into a movement across Europe and the GCC. Vetted through our VECTOR7™ Signal Stack, you’re not just hired, you’re chosen. This is more than work. This is where builders build the future.

About the Role

Our client is seeking a Mobile Developer for a high-impact, freelance assignment in Brussels. This is a 3-month, on-site opportunity to architect and deliver native Android and/or iOS applications focused on real-time communication and robust, microservice-driven backends. You’ll be at the heart of a mission-critical project, shaping the way users connect and interact, regardless of network conditions. If you thrive on building resilient, high-availability mobile solutions and want to be part of a builder-first movement, this is your stage.

Why This Role Matters

This role is pivotal in delivering seamless, real-time communication experiences to users who depend on reliability and performance. You’ll be solving complex challenges around connectivity, offline-first access, and secure authentication — ensuring that mission-critical applications remain available and responsive at all times. Your expertise will directly impact user satisfaction, business continuity, and the future of mobile technology for our client.

Key Responsibilities

• Develop native Android and/or iOS applications with a strong focus on real-time communication (text, voice, video) and microservice-oriented backend integration
• Distribute and optimize applications for a range of mobile devices, including smartphones and tablets
• Version and document source code for multiple projects, ensuring maintainability and clarity
• Support colleagues and end users, providing technical guidance and troubleshooting
• Meet project deadlines and deliver high-quality, production-ready code
• Mentor team members, sharing knowledge and best practices with clarity and pedagogy

Technical Skills

• Confirmed experience in native Android development
• Proficiency in Kotlin Multiplatform (KMP)
• Strong command of Java
• Experience with Compose, MVVM, and Clean Architecture
• Understanding of microservice-oriented backend architectures
• Expertise in real-time data transmission (text, voice, video) and user notifications
• Experience with mission-critical, high-availability mobile applications
• Offline-first storage mechanisms (e.g., SQLite)
• Modern authentication concepts (OpenID, JWT for mobile)
• CI/CD principles and Git version control
• Design and maintenance of robust unit tests
• Familiarity with reactive programming and websockets
• Additional asset: Experience with other mobile frameworks

Language Proficiency

• Excellent command of French (fluid, natural communication)
• Fluent in technical English (active knowledge)
• Passive knowledge of Dutch is a plus

Other Requirements

• Bachelor’s degree in Computer Science or related field
• Proven experience in a similar mobile development role
• Strong mentoring and knowledge-sharing abilities
• On-site presence in Brussels required (no remote option)

This is a freelance position for a 3-month project based in Brussels. At RELYzIT Talent, we place elite tech talent in roles that drive real impact and innovation. Join a community where builders build the future.

Ready to build the future? Upload your CV and join the movement.

#RELYzIT #TechJobs #FreelanceTalent #Brussels #Android #Kotlin #iOS #MVVM #CI/CD #MobileDevelopment #RealTimeCommunication