Zymr developed Azure-based node.js microservices for various services - registration of beacon IoT devices, multi-tenancy, analytics, and other administrative services. Extensive REST-APIs were developed to enable merchants to integrate with Favendo's core platform, especially for real-time marketing campaigns to consumers in shopping malls and retail stores. We built an analytics tier using Azure streaming analytics and AI/ML models to process real-time logs from various BLE sensors and corresponding mobile apps of consumers visiting retail stores. We developed a Python-based IoT simulator to generate random location-aware logs.Using a Python-based test automation framework, we successfully scaled the analytics engine to 1000+ stores with 100K BLE sensors.Zymr was chosen as the sole developer of Favendo's Azure cloud-native analytics platform for the retail industry. This platform tracks visitors in malls and stores, and integrates the real-time analytics with merchant's proximity marketing applications. We brought its IoT expertise and leveraged Favendo's IoT BLE and iBeacon sensors that were provisioned from the cloud. Merchant-specific iOS and Android applications used these sensors automatically to track their movement in stores. Our teams developed a merchant-side admin portal for Shopping Mall or Retail Outlet to provide rich location-based visualization of foot traffic, dwell-times, and demographics for proximity marketing. Our client's retail customers leverage this real-time Location Service, a BLE IoT solution, to create a powerful proximity marketing platform to assist retailers in tailoring their product placement and developing digital marketing and retail promotional programs.