Senior Mobile App Developer (Kotlin)

Experience: 7+ years
Project Duration: October 1, 2026 – February 28, 2027
Format: Remote
Location: Poland

About the Project

We are looking for a Senior Mobile App Developer with strong Android and Kotlin expertise to join a long-term project focused on developing modern, secure, and scalable enterprise mobile applications.

You will work closely with cross-functional teams to build core mobile features, integrate backend services and authentication solutions, and continuously improve application performance, security, and usability.

Responsibilities

• Design and develop core mobile application features using modern Android technologies
• Collaborate with cross-functional teams to integrate APIs, authentication flows, and backend services
• Build and maintain scalable, secure, and high-performance mobile solutions
• Ensure application maintainability, accessibility, and usability across multiple languages and platforms
• Contribute to testing, monitoring, troubleshooting, and continuous improvement of the application
• Participate in Agile/Scrum/SAFe development processes and collaborate with distributed teams

Requirements

• 7+ years of software development experience, including significant Android development experience
• Expert-level knowledge of Kotlin and modern Android development practices
• Experience with Kotlin Multiplatform is preferred; candidates with Kotlin and some Swift experience may also be considered
• Strong knowledge of Android SDK, Jetpack components, Kotlin Coroutines, Flow, and MVVM
• Experience developing scalable, secure, and maintainable enterprise-grade mobile applications
• Strong experience with REST APIs, backend integrations, authentication, and mobile security
• Deep understanding of mobile application performance optimization, monitoring, and troubleshooting
• Experience implementing accessibility and usability best practices
• Familiarity with testing tools and frameworks such as JUnit, Espresso, and UI automation tools
• Experience working in Agile/Scrum/SAFe environments and complex cross-functional teams
• Fluent English and willingness to participate in meetings during US working hours

Nice to Have

• Experience with WebView
• Experience integrating third-party identity providers such as Entra, Auth0, or Okta
• Knowledge of biometric authentication, OpenID, and FIDO2 passkey flows
• Experience building multilingual applications, e.g. supporting English and Spanish
• Knowledge of Azure, Firebase, App Center, or similar platforms
• Healthcare, MedTech, or other regulated industry experience

Tech Stack

• Android
• Kotlin
• Android SDK
• Jetpack / Jetpack Compose
• Kotlin Coroutines
• Flow
• MVVM
• REST APIs
• Mobile Security
• JUnit / Espresso

Location

• Remote from Poland
• The candidate must be willing to attend late meetings with the client's US commercial and development teams