Tac Jiang

Senior Mobile Developer at PayByPhone Technologies Inc.

Architected and scaled a high-traffic iOS app serving 5M+ users across 12 languages, with core modules for user and vehicle management and PCI-compliant multi-channel payments. Implemented GPS-based parking features with real-time search, low-connectivity optimization, and BLE interaction with meters. Built camera-based payment workflows (credit card recognition, location number detection, QR scanning). Delivered companion apps for Apple Watch and CarPlay. Employed MVVM with Core Data and RESTful APIs for modular, offline-capable performance; automated CI/CD with Fastlane and Git; emphasized TDD with XCTest and XCUITest.

Senior Mobile Developer at nTrust Group

Built and deployed a global mobile payment app for 200K+ users across North America, Europe, and Asia. Developed P2P transfers, currency conversion, merchant promotions, QR code scanning, and social integrations. Integrated online banking and credit card processing via RESTful APIs, collaborating closely with backend teams. Designed responsive interfaces supporting all iOS screen sizes. Managed App Store deployment and led a 3-person mobile team through delivery cycles.

Senior Mobile Developer at TRG Mobilearth Inc.

Built and maintained iOS and Android apps for 100K+ users across 15 credit unions. Developed core mobile banking features including payments, credit scoring, remote check deposit, digital signatures, account balance, SMS alerts, and ATM locators. Created project documents, requirements, and delivery plans; implemented backend systems for user management, transaction tracking, and financial reporting. Deployed over 10 iOS apps and led a 2-person mobile development team.

Senior Software Developer at InsidersLab Corp.

Developed a financial reporting system generating 10,000+ daily stock reports with insider transactions and interactive charts. Built an iOS app to visualize stock data, and managed a 120K+ subscriber base with payment processing and email alerts. Improved SEO and user acquisition via Google Analytics and social channels; administered Linux-based servers with maintenance and monitoring.

Software Developer at ANV Security Group Inc.

Developed a real-time video surveillance system with live monitoring, instant storage, and remote sharing using 3G-enabled mobile DVRs and IP cameras. Integrated payment processing, VoIP, SMS, and Google Maps APIs into the application layer; provided customer support and timely issue resolution.

Senior Mobile Developer at PayByPhone Technologies Inc.

Architected and scaled a high traffic iOS app serving 5M+ users and processing 100M+ annual transactions in global markets, with support for 12 languages. Led core modules including user and vehicle management for fleets and individual users, and multi-channel payments (credit card, Apple Pay, PayPal) with PCI compliant security. Implemented GPS and Map parking features with real time search, low connectivity optimization, and BLE-based hardware interaction at parking meters. Developed camera-based features including credit card recognition, location number detection, and QR code scanning for seamless parking and payment workflows. Delivered companion apps for Apple Watch and CarPlay, enhancing driver accessibility and mobility. Implemented MVVM architecture supported by Core Data and RESTful APIs to enable modular and offline-capable performance. Automated CI/CD with Fastlane and Git, ensuring code quality through TDD with XCTest and XCUITest.

Senior Mobile Developer at nTrust Group

Built and deployed a global mobile payment app for 200K+ users across North America, Europe, and Asia. Developed core features including P2P transfers, currency conversion, merchant promotions, QR code scanning, and social integrations. Integrated online banking, credit card processing, and location services via RESTful APIs, working closely with backend teams. Designed responsive interfaces using multiple Storyboards, Auto Layout to support all iOS screen sizes. Managed App Store deployment and led a 3-person mobile team through delivery and iteration cycles.

Senior Mobile Developer at TRG Mobilearth Inc.

Built and maintained iOS and Android apps for 100K+ users across 15 credit unions in North America. Developed core mobile banking features including payments, credit scoring, remote check deposit, digital signatures, account balance, SMS alerts, and ATM locators. Designed project documentation, including requirements, user flows, technical diagrams and delivery plans. Implemented backend systems for user management, transaction tracking, and financial reporting. Managed deployment of over 10 iOS apps to the App Store and led a 2-person mobile development team.

Senior Software Developer at InsidersLab Corp.

Developed a financial reporting system that generated over 10,000 daily stock reports featuring insider transactions, market analysis, and interactive financial charts. Built an iOS app to access and visualize stock data retrieved from backend services. Managed a subscriber base of 120K+ users, supporting payment processing and email alert workflows. Improved SEO rankings and user acquisition through Google Analytics, YouTube, Facebook, Twitter, and RSS integration. Administered Linux-based web and database servers, including process monitoring, scheduled cron jobs, and system maintenance.