Freelance Mobile App Developer (iOS / Android)

Role Overview

Freelance (part-time) Mobile App Developer for the Tendem project (Tendem AI). Build and refine native and cross-platform mobile applications for iOS and Android, applying mobile engineering skills to deliver stable, performant, user-friendly apps.

Responsibilities

• Design, build, and iterate mobile applications for iOS, Android, or both (native or cross-platform)
• Build apps using React Native, Flutter, Swift (iOS), or Kotlin (Android)
• Create responsive UIs following platform conventions (iOS HIG, Material Design)
• Integrate native device features: camera, push notifications, location, storage, biometrics
• Connect to backend services via APIs; implement offline state, caching, and synchronization
• Implement monetization features when required: in-app purchases, ads, subscriptions
• Debug, optimize, and refactor for correctness, performance, battery efficiency, and maintainability
• Handle platform-specific issues and prepare distributions (TestFlight, Play Console)

Requirements

• 3+ years of relevant mobile app development experience
• Hands-on experience shipping iOS and/or Android apps
• Strong knowledge of mobile UI patterns, navigation, and state management
• Experience integrating REST APIs, working with async data, and local storage
• Familiarity with native device APIs (notifications, camera, location, storage, biometrics)
• Experience with mobile build tools, code signing, and app store submission
• Ability to implement in-app purchases/ads/subscriptions (in-app monetization experience is a plus)
• Portfolio of shipped mobile apps (required; App Store / Google Play links preferred)
• English proficiency at B2 or above

Nice to Have

• Backend familiarity with Firebase, Supabase, or similar
• Experience with Kotlin + Jetpack Compose and/or SwiftUI is advantageous depending on your target platform

Expectations & Compensation

• Estimated 10–20 hours/week during active project phases
• Pay up to $60/hour equivalent depending on level and contribution pace