● Built user flows for viewing, purchasing, and activating numbers, increasing customer acquisition and reducing seller workload. ● Delivered seamless mobile number porting functionality from other operators. ● Implemented SIM replacement (physical to eSIM). ● Integrated face and ID recognition for simplified customer service. ● Designed and built advanced iOS applications using modern architectures (VIPER, VIP, MVC, Clean). ● Worked with third-party frameworks (verification, identification, data sources, APIs). ● Evaluated and implemented new technologies to improve development efficiency. ● Collaborated with product management, design, tech, and architecture teams. ● Embedded self-service flows. ● Participated in end-to-end agile development of iOS mobile applications. ● Upgraded transaction history, filtering, and detail manipulation features. ● Integrated new designs and implemented features based on customer needs. ● Developed multi-module applications. ● Wrote unit tests for robustness, edge cases, usability, and reliability. ● Integrated RESTful APIs, Crashlytics for bug tracking. ● Created reusable custom UI classes, extensively using graphics contexts and layers. ● Implemented OAuth2 authentication (Facebook, Google, VK, Mail.ru). ● Integrated mobile payment frameworks (EPAY KKB). ● Supported different app flows for multiple user roles.