Google Cloud Monitoring (formerly Stackdriver) is Google Cloud's native observability platform, providing GCP-wide metric collection, Cloud Logging log management, and Error Reporting, with Managed Prometheus and Grafana integration.
Azure Monitor is Microsoft Azure's full-stack monitoring platform, providing VM, AKS, and application metrics, log analytics, and Application Insights APM, deeply integrated with the Azure ecosystem.
Amazon CloudWatch is AWS's native monitoring and observability service, providing metrics, logs, and alarm management across 200+ AWS services, with Logs Insights analysis and X-Ray distributed tracing.
Datadog, founded in 2010 and headquartered in New York, USA, is a leading cloud monitoring and observability platform offering infrastructure, APM, log and security monitoring with 3000+ integrations and 30000+ enterprise customers.