Senior Mobile Engineer - React Native in City of London

The Challenge

Healthcare delivery increasingly depends on continuous patient engagement and real-time health monitoring outside traditional clinical settings. As wearable devices and health tracking capabilities proliferate, the industry needs engineers who can build secure, reliable mobile experiences that seamlessly connect patients, their health data, and AI-powered clinical insights into a unified care journey.

The Opportunity

Build Onsera's mobile application that empowers patients to actively manage cardiometabolic conditions through connected health devices and AI-driven insights. You'll own the development of iOS and Android applications that integrate with Apple HealthKit, Google Health Connect, and a range of connected devices—digital scales, blood pressure cuffs, activity trackers, and continuous glucose monitors. Working closely with ML engineers, you'll create robust interfaces to internal AI APIs that transform patient data into actionable health recommendations. This role offers the opportunity to shape the full mobile experience while collaborating with product, design, and clinical teams to deliver features that meaningfully improve patient outcomes.

What You'll Do

• Build and ship features for iOS and Android mobile applications serving patients managing cardiometabolic conditions.
• Own integrations with Apple HealthKit and Google Health Connect, enabling seamless data synchronization from digital scales, blood pressure cuffs, activity trackers, and continuous glucose monitors (CGMs).
• Partner with machine learning engineers to design and implement client-side integrations with internal AI APIs for data analysis, personalization, and clinical decision support.
• Drive end-to-end feature delivery in an agile environment, from requirements gathering through deployment and monitoring.
• Collaborate closely with product and design teams to translate user requirements into technical specifications and implementation plans.
• Establish mobile development best practices, including testing strategies, code quality standards, and deployment pipelines.
• Take ownership of technical decisions and proactively identify opportunities to improve app performance, reliability, and user experience.

Minimum Qualifications

• 5+ years of experience building production mobile or full-stack applications with modern frameworks.
• Strong proficiency in mobile development with demonstrated experience shipping iOS and/or Android applications.
• Track record integrating health device APIs such as Apple HealthKit or Google Health Connect (or similar health data platforms).
• Experience with RESTful API design and integration, including real-time data synchronization patterns.
• Proven ability to collaborate with cross-functional teams (product, design, ML) in an agile development environment.
• Familiarity with cloud platforms (GCP, AWS, or Azure) and deploying applications to production.
• Demonstrated ownership mindset with ability to drive projects from concept through launch.

Preferred Qualifications

• Experience with Typescript / React Native, Flutter, or native iOS/Android development.
• Strong written and verbal communication skills for technical collaboration across engineering, product, and clinical teams.
• Experience working with machine learning APIs or integrating AI/ML capabilities into consumer applications.
• Background in healthcare technology or regulated industries (HIPAA compliance, FDA guidance).
• Track record building applications that handle sensitive health data with appropriate security and privacy controls.
• Familiarity with continuous glucose monitor (CGM) data processing or metabolic health applications.
• Understanding of mobile app analytics, crash reporting, and performance monitoring.

What We Offer

• Mission-driven work addressing critical healthcare challenges in cardiometabolic care and weight management.
• Ownership of the core patient-facing mobile experience serving thousands of members.
• Direct collaboration with ML engineers, clinicians, product managers, and designers.
• Growth opportunities in a fast-paced, early-stage environment with significant technical and leadership responsibility.
• Competitive salary and benefits package, including participation in our equity program.

About Onsera Health

We are an early-stage health AI company revolutionizing cardiometabolic care and population health economics connected to weight loss. Our unique position within the PHP ecosystem provides:

• Venture track record: A proven track record of success in building biotech and healthcare companies.
• Deep capital: Funding and resourcing to support deep tech and scientific R&D—and to drive growth.
• Strategic guidance: Direct access to industry pioneers (including founders of The Medicines Company and Metsera), healthcare experts (including leaders in virtual care, former FDA commissioners), strategists (McKinsey/QuantumBlack alumni), and world-class scientific talent (e.g., scientific leaders at Ellison Institute of Technology, Oxford University, key opinion leaders in metabolic and cardiovascular disease).
• Expert network: Established connections across pharma, payers, and providers.
• Startup agility: Ownership in the venture, founder mentality, and ground-floor impact.

About PHP

Population Health Partners (PHP) is a premier investment firm established in 2020, aimed at transforming health outcomes for large populations. With offices in New York and London, PHP combines financial resources with industry-leading capabilities and technology. The firm's incubation portfolio includes Metsera and Corsera Health.

Leadership: Led by industry veterans including Clive Meanwell (The Medicines Company), Chris Cox (The Medicines Company), and Whit Bernard (Metsera), bringing decades of founder experience and operational excellence in biopharma and healthcare, and Roy Berggren, 30+ year McKinsey Healthcare leader.