Senior Mobile Developer (Android & iOS)

AERONES is seeking a hands-on Senior Mobile Developer to build and evolve the field app our technicians rely on every shift, on both Android and iOS. In this role, you will build our new native iOS app in Swift and SwiftUI, modernise our large existing Android app in Kotlin step by step, own offline-first behaviour and sync on both platforms, and use AI coding agents as your main way of working.

Our technicians often work offline on remote wind turbine sites, so the app has to work without a connection and sync reliably when it comes back. Both apps must behave the same, with one data model, one API contract and one set of sync rules, and you will be the person who makes that true.

What You’ll Do

• Build the native iOS app in Swift and SwiftUI to feature parity with Android, starting with the core technician flows, piloting it through TestFlight and releasing it on the App Store.
• Modernise the Android app step by step, moving from XML views to Jetpack Compose and from RxJava to coroutines and Flow, with every step releasable on its own.
• Own offline-first behaviour on both platforms: local storage, background sync, and conflict handling when office staff or other technicians edit the same work orders.
• Define the shared contract both apps follow, covering the data model, sync protocol, validation rules and error handling.
• Agree GraphQL contracts with the backend team, including data shapes, versioning and sync endpoints.
• Agree acceptance criteria directly with technicians and supervisors, and verify the result in the field.
• Automate builds, tests and store releases for both platforms so shipping is fast and predictable.

What You’ll Need to Succeed

• 7+ years of professional native mobile development. With apps having more than 5k daily users.
• Production Android apps shipped to Google Play with Kotlin, Jetpack Compose, coroutines and Flow, Room and WorkManager.
• Hands-on experience with Swift, SwiftUI, Swift Concurrency (async/await), Core Data or SwiftData and background tasks, and the ability to build an iOS app to production standard.
• Proven experience building offline-first apps with local databases, background sync, conflict resolution and strong data integrity in production.
• Daily use of AI coding agents in production work, with concrete examples of how you review and verify their output.
• Experience gradually migrating an existing app you did not write, shipping each step to real users.
• Solid grounding in modern app architecture, such as MVVM or MVI, clean layering and modularisation, and in integrating GraphQL (Apollo Kotlin or Apollo iOS) or REST APIs, including authentication, versioning and error handling.
• Habitual use of unit, integration and UI tests (JUnit, Espresso and Compose tests; XCTest and XCUITest), especially for sync and failure cases.
• An ownership mindset and fluent English, with the judgement to make trade-offs across two platforms and explain them clearly to technicians, supervisors and the backend team.

What We Offer

• Competitive pay with a salary of €4000–€5500 gross/month.
• Global impact through robotics shaping the future of renewable energy.
• Career growth with real opportunities to learn, develop, and advance.
• Cutting-edge technology with hands-on experience in innovative robotics.
• Enjoy the journey with team events, celebrations, and a vibrant company culture.
• Health insurance after your probation period.
• Extra time to recharge with additional Health Recovery Days.
• Learning support with paid study leave.
• Life-event benefits to support you when it matters most.

Ready to make an impact? If you’re excited about solving real challenges, working with great people, and contributing to technology shaping the future of renewable energy, we’d love to hear from you. Apply and let’s build what’s next together.