Zain Bahrain is the official mobile application of a leading telecommunications operator in the Kingdom of Bahrain, allowing users to manage their telecom services seamlessly. I contributed to the development of key modules including authentication, bill payment, consumption tracking, and recharges. I integrated region-specific payment SDKs for the MENA market in compliance with Bahraini banking regulations, and conducted mobile security audits implementing best practices according to the OWASP Mobile Security Testing Guide. The app is available on both Google Play Store and App Store