Our custom IoT Cloud Application Using Siemens PLC bridges the gap between field-level control and cloud analytics. Utilizing the secure MQTT, OPC UA, or HTTPS protocols, it enables Siemens SIMATIC PLCs to stream status, sensor telemetry, and diagnostics data directly to AWS, Azure, or private cloud portals. This solution facilitates edge processing, predictive analytics, remote machine control, and historical data logging without compromising local control safety boundaries.