Senior Mobile Engineer – React Native, Expo, TypeScript

easybill GmbH

. Develop and enhance easybill-mobile using React Native, Expo, and TypeScript for iOS and Android .

Posted 10/28/2026contractRemote • GermanySeniorWebsite

Core Competencies

Role fit

Core Competencies

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Demonstrates extensive experience in developing mobile applications using TypeScript, React Native, and Expo, with a strong focus on REST API integration, performance optimization, and secure data management. Proficient in automated testing and maintaining high-quality code while ensuring accessibility and multilingual support.

Highest-signal resume keywords

TypeScriptReact NativeExpoREST API IntegrationAutomated Testing

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills

TypeScriptReact NativeExpoREST APIPHPSymfonyAutomated TestingMobile Application DevelopmentPerformance OptimizationComponent Architecture

Soft Skills

Clear CommunicationIndependent Working StylePragmatic Problem Solving

Tools & Technologies

Claude CodeEASSimulatorsApp Stores

Industry Keywords

Mobile WorkflowsData ManagementMultilingual SupportApp Store PublishingOpen-Source Contributions

Tech Stack

Tools & technologies

AndroidiOSKotlinPHPReactReact NativeSwiftSymfonyTypeScript

About the role

Key responsibilities & impact

Develop and enhance easybill-mobile using React Native, Expo, and TypeScript for iOS and Android
Translate requirements related to invoices and documents into intuitive mobile workflows and high-quality native interfaces
Evolve the app architecture and create maintainable structures for navigation, reusable components, forms, and data access
Integrate the REST API and ensure reliable data management, including typed interfaces, validation, caching, loading states, and error handling
Work at the intersection of the app and backend
Extend the REST API with PHP and Symfony as needed
Develop secure authentication and session management, while handling sensitive customer and business data with care
Account for performance and platform-specific considerations across changing network connections, app switching, and different devices
Ensure accessibility and multilingual support
Safeguard changes through automated tests and testing on simulators and real devices
Help shape build, release, and monitoring processes through publication in the app stores
Challenge requirements, contribute your own solution proposals, and support features from initial concept through release and ongoing development
Make intensive use of AI tools such as Claude Code, while taking responsibility for the quality, clarity, and accuracy of the results

Requirements

What you’ll need

Freelancer / self-employed contractor
Extensive senior-level experience with TypeScript, React Native, and Expo
Experience taking mobile applications beyond implementation through to release
Understanding of React, component architecture, state management, and asynchronous data flows
Knowledge of iOS and Android specifics, with a systematic approach to performance issues, platform bugs, and debugging
Proficient in REST API integration, with an understanding of API contracts, authentication, validation, and error handling
Ability to independently understand existing API endpoints, analyze issues between the app and backend, and extend interfaces independently
Experience with automated testing, traceable technical decisions, and maintainable code
Independent, pragmatic working style and clear communication
Fluent German and good English skills
Ideally, knowledge of PHP and Symfony
Additional advantages: experience with EAS, native modules in Swift or Kotlin, app store publishing, and mobile release processes
Published apps, open-source contributions, or public experiments on GitHub are welcome

Benefits

Comp & perks

Remote-first team – no location-based restrictions
An inspiring and flexible work environment based on trust and personal responsibility
The opportunity to help shape the company’s strategy and culture
A committed team and the opportunity to work together on innovative solutions
Regular team events