Mobile Application Developer

Mobile Developer / Mobile Tech Lead – iOS & Android Location: Helsinki, Finland (Hybrid – 50% Remote / On-site in Helsinki) Contract Duration: 15 Oct 2026 – 15 Apr 2027 (Freelance B2B Contract, extension potential) Workload: Full-Time (100% / 37.5 Hours per Week) Languages: Fluent English (Mandatory) Position Summary: We are seeking a Senior Mobile Developer / Mobile Tech Lead with dual-platform expertise across iOS (Swift) and Android (Kotlin) for a contract assignment based in Helsinki. In this role, you will combine hands-on development with technical leadership to drive the UI uplift, modernization, and architecture of core mobile digital banking applications. Key Responsibilities: Lead UI improvement initiatives to deliver a consistent, modern, and user-friendly experience across mobile platforms. Design, develop, and maintain features for iOS ( Swift ) and Android ( Kotlin ) applications. Contribute to mobile architecture patterns ( MVVM, VIPER ), technical designs, code reviews, and continuous improvement frameworks. Ensure high quality through unit testing, UI test automation, REST API integration, and performance/security optimization. Take full ownership of delivered solutions, including implementation, testing, deployment, and post-launch support. Qualifications & Requirements: Mobile Seniority: 7+ years of professional experience in mobile application development with a proven track record of delivering large-scale solutions. Dual-Platform Mastery: Deep expertise in primary native stack ( Swift or Kotlin ) combined with strong hands-on capability in the other. UI Modernization Track Record: Experience leading or driving UI modernization, redesign, or uplift initiatives in mobile apps. Architectural & UI Frameworks: Solid knowledge of MVVM/VIPER , UIKit/Auto Layout , Jetpack Compose , XML layouts, and Fragments. Quality & Integration: Strong understanding of unit testing, UI test automation, REST API integration, and mobile security practices. Domain Knowledge (Desirable): Previous experience in banking, payments, or financial services IT solutions is a strong advantage. If you are interested, or you know someone that could be, please reach out and we can arrange a time to speak soon?