Senior Mobile Engineer (iOS & Android)

About the role

AgileEngine is seeking a Senior Mobile Engineer to maintain and enhance native iOS and Android voice‑messaging applications. The role focuses on Swift (70%) and Kotlin (30%) while leading proof‑of‑concept work for a potential migration to React Native.

Key responsibilities

• Maintain, enhance, and optimise existing native iOS (Swift) and Android (Kotlin) applications.
• Design and deliver Proof‑of‑Concepts to evaluate a transition to React Native.
• Implement and optimise real‑time communication features, including WebRTC, SIP, and in‑app chat.
• Resolve complex voice‑related issues such as VoIP push notifications, socket reliability, and network latency.
• Collaborate directly with client stakeholders on mobile architecture and feature decisions.
• Conduct code reviews, establish best practices, and drive continuous performance improvements.
• Participate in an Agile delivery workflow with regular sprint planning and technical iterations.

Required profile

• 3+ years of professional mobile development experience on both iOS and Android.
• Strong hands‑on experience with Swift and Kotlin (role split 70% Swift, 30% Kotlin).
• Exposure to React Native and interest in cross‑platform migration.
• Solid background in real‑time communication (WebRTC, SIP, VoIP).
• Experience implementing voice‑enabled push notifications (PushKit, CXProvider, VoIP background modes).
• Ability to troubleshoot network latency and socket reliability issues.
• Based in LATAM or Ukraine with at least 4 hours overlap with EST.
• Excellent written and spoken English for client‑facing collaboration.

Required skills

• Swift
• Kotlin
• React Native
• WebRTC
• SIP
• VoIP
• PushKit
• CXProvider
• Socket programming
• Agile development