Full Stack Mobile Developer; iOS & Android

Job Role

Full Stack Mobile Developer (iOS & Android) — .NET on GCP

Sheffield, UK

3+ Years of experience building mobile apps for both iOS and Android, using native and/or cross-platform approaches.

Hybrid

Not open for sponsorship case

At Synechron, we believe in the power of digital to transform businesses for the better. Our global consulting firm combines creativity and innovative technology to deliver industry‑leading digital solutions. Synechron’s progressive technologies and optimisation strategies span end‑to‑end Artificial Intelligence, Consulting, Digital, Cloud & Dev Ops, Data, and Software Engineering, servicing an array of noteworthy financial services and technology firms. Through research and development initiatives in our Fin Labs we develop solutions for modernisation, from Artificial Intelligence and Blockchain to Data Science models, Digital Underwriting, mobile‑first applications and more.

Over the last 20+ years, our company has been honoured with multiple employer awards, recognising our commitment to our talented teams. With top clients to boast about, Synechron has a global workforce of 14,700+ and has 55 offices in 20 countries within key global markets. For more information on the company, please visit our website or Linked In community

Diversity & Inclusion are fundamental to our culture, and Synechron is proud to be an equal opportunity workplace and an affirmative‑action employer. Our Diversity, Equity, and Inclusion (DEI) initiative ‘Same Difference’ is committed to fostering an inclusive culture – promoting equality, diversity and an environment that is respectful to all. We strongly believe that a diverse workforce helps build stronger, successful businesses as a global company.

We encourage applicants from across diverse backgrounds, race, ethnicities, religion, age, marital status, gender, sexual orientations, or disabilities to apply. We empower our global workforce by offering flexible workplace arrangements, mentoring, internal mobility, learning and development programmes, and more. All employment decisions at Synechron are based on business needs, job requirements and individual qualifications, without regard to the applicant’s gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law.

Design, build, and maintain high‑quality mobile applications across iOS and Android, working end‑to‑end from mobile UI through to integration with backend services running on .NET and hosted on Google Cloud Platform (GCP). You’ll collaborate closely with product, design, backend, and cloud teams to deliver secure, performant, and scalable mobile experiences.

• Design and develop high‑performance, scalable mobile applications for iOS and Android
• Build and maintain reusable mobile components, UI patterns, and app architecture aligned to engineering standards
• Integrate mobile apps with backend services on GCP using REST/JSON (and where relevant GraphQL), including authentication and secure data handling
• Contribute to backend/API integration work (and occasionally service improvements) in a .NET ecosystem to support mobile features
• Ensure reliability, responsiveness, and strong user experience across a range of devices, OS versions, and network conditions (including offline considerations where needed)
• Implement automated testing, participate in code reviews, and support CI/CD pipelines and release processes
• Monitor and optimise app performance, stability, battery usage, and telemetry; troubleshoot production issues
• Ensure compliance with enterprise security, data privacy, and secure coding practices
• Contribute to agile ceremonies (planning, refinement, stand‑ups) and deliver iteratively with the team

3+ years’ experience building mobile apps for both iOS and Android, using native and/or cross‑platform approaches.

• Native:
  Swift/SwiftUI (iOS), Kotlin/Jetpack (Android)
• Cross‑platform (nice to have):
  Angular
• Strong understanding of mobile app architecture, design patterns, performance optimisation, and debugging
• Solid experience integrating mobile apps with backend services via RESTful APIs, JSON, and secure authentication flows (e.g., OAuth2/OIDC concepts)
• Working knowledge of .NET backend development and API fundamentals (able to collaborate effectively and contribute where needed)
• Familiarity with GCP‑hosted services and mobile‑relevant cloud components (e.g., Firebase, Cloud Functions, Pub/Sub or equivalents)
• Experience with CI/CD and release tooling (e.g., Git Hub Actions, Fastlane, Bitrise, Azure Dev Ops or similar)
• Understanding of security best practices for mobile (secure storage, certificate pinning awareness, threat modelling mindset)
• Strong communication skills and a collaborative approach across engineering, product, and other functions