Android Engineer – Kotlin, Java, Kotlin Multiplatform

Tech4Good (Hybrid, London)

£80,000–£95,000 + 10% Bonus

2 Days per Week in London Office

A global, mission-driven health tech company is looking for an experienced Android Engineer to help power the next generation of its member-facing mobile app. This is a tech-4-good based app helping people with addiction.

The company has supported more than 750,000 members, partners with hundreds of employers and health plans.. With continued growth following its recent Series C, the engineering team is expanding in London to support major product evolution, including a strategic transition to Kotlin Multiplatform (KMP) and Compose Multiplatform (CMP).

The Role

As an Android Engineer, you’ll play a critical role in shaping a high-impact mobile product used daily by members around the world. You’ll work closely with Android, iOS, backend, platform, product and design teams to deliver fast, reliable and engaging features, while contributing to the company’s cross-platform strategy.

This role is hands-on, technically challenging, and ideal for someone who wants to blend modern Android development with emerging cross-platform frameworks.

Company Culture & Values

You’ll join a collaborative, transparent and impact-driven engineering team where ideas are valued, experimentation is encouraged, and the mission sits at the heart of everything.

The company’s mission is to make substance use treatment accessible, effective and personalised.

Key Responsibilities

• Build and maintain the Android application, ensuring a world-class member experience.
• Contribute to new cross-platform development using KMP and CMP.
• Implement new features with clean, maintainable, high-quality Kotlin code.
• Collaborate with product managers and designers to refine wireframes and propose scalable solutions.
• Integrate REST APIs and work closely with backend and platform teams to optimise performance.
• Maintain and enhance CI/CD pipelines using Bitrise.
• Participate in code reviews, design discussions, and agile ceremonies.
• Help define architectural patterns to support ongoing cross-platform evolution.

Role Requirements

• 4+ years of professional Android development experience.
• Strong Kotlin proficiency (plus working knowledge of Java).
• Good understanding of Android architecture patterns such as MVVM and Clean Architecture.
• Experience with Jetpack Compose, Hilt, Retrofit, and core Android libraries.
• Exposure to or enthusiasm for Kotlin Multiplatform and Compose Multiplatform.
• Experience with REST API integration and modern networking/data layers.
• Familiarity with CI/CD tools (Bitrise or equivalent).

Bonus Skills

• Production experience with KMP or CMP.
• Knowledge of SQLDelight, Room, Koin or similar tools.
• Experience improving Gradle build performance.
• Understanding of iOS concepts for cross-platform collaboration.
• Awareness of mobile security and performance best practices.

Benefits & Perks

• £80,000–£95,000 salary
• Minimum 10% annual bonus
• Stock options
• Hybrid working (2 days per week in London)
• Professional growth opportunities
• Quarterly in-person team events
• Work on a product directly improving lives every day