To strengthen the team, we are currently seeking an experienced Senior App Developer (m/f/d) for our client, who will develop innovative, bespoke mobile and web applications and make a significant contribution to technological goals of his clients. Job description: End-to-end development of mobile and web applications with a focus on scalability, performance, and user-friendliness. Technical conception, architecture, and implementation of new features, as well as the further development of existing apps. Leading agile development teams and providing technical consultancy on best practices in app development. Ensuring quality through code reviews, unit tests, and continuous integration and deployment (CI/CD). Analysing customer requirements and developing technical specifications in close collaboration with product managers and other stakeholders. Integrating interfaces with third-party systems (e.g., REST APIs, web services ) and supporting cloud connectivity (e.g., AWS, Azure ). Publishing and maintaining mobile apps on the Google Play and Apple App Store platforms, as well as optimising the apps for App Store Optimisation (ASO). Implementing security requirements (e.g., data protection, authentication ) and performance optimisation. Skills requested: Completed degree in Computer Science, Software Engineering, or a comparable qualification. At least 5 years of experience in the professional development of mobile or web applications. In-depth knowledge of programming languages such as Java, Kotlin, Swift, Objective-C, JavaScript, TypeScript, or other modern frameworks. Experience with cross-platform development tools like React Native, Flutter, or Xamarin. Solid knowledge of backend technologies ( Node.js, Python, Java ) as well as databases ( SQL, NoSQL ). Experience in the publication of apps on Google Play and Apple App Store, as well as their maintenance and updates. Proficient in using version control systems (e.g., Git ) and modern development environments. Experience with cloud services (e.g., AWS, Google Cloud, Azure ) and CI/CD pipelines. Strong analytical skills and a structured, solution-oriented working style. Experience in project management and leading development teams is an advantage. Moderate German skills (B1) and very good English skills (C1). The ETA Personal GmbH The ETA Personal GmbH is a renowned personnel recruitment agency specializing in highly qualified experts in the fields of engineering, IT, power infrastructure, automotive and automation. With a focus on the German market, our team searches worldwide for highly skilled professionals to meet the requirements and needs of our clients. We understand the complexity of the industry and work closely with companies to identify and place the right talents. ETA Personal GmbH is your trusted partner for recruiting experts who can master the challenges and innovations in high-tech sectors. Become an App Pioneer – Act Now Do you have what it takes to develop apps that will change the digital world? Do you want to not just be part of the progress but to drive it forward? Then seize the opportunity now and join the dynamic team of our client Do not wait any longer – send us your CV. Show us what you’re made of, and help us shape the apps of the future Apply now and set your career on the path to success