Zipkin vs Kiali: What are the differences?
Zipkin: A distributed tracing system. It helps gather timing data needed to troubleshoot latency problems in service architectures. Features include both the collection and lookup of this data; Kiali: Service mesh observability and configuration. It is an observability console for Istio with service mesh configuration capabilities. It helps you to understand the structure of your service mesh by inferring the topology, and also provides the health of your mesh.
Zipkin and Kiali can be categorized as "Monitoring" tools.
Zipkin is an open source tool with 11.5K GitHub stars and 2.09K GitHub forks. Here's a link to Zipkin's open source repository on GitHub.