The following list gathers some service meshes examples that are used or have been used to test or demo Kiali. There is no guarantee that all of them are still working at any time, they may (or may not) be supported by their respective owners.
From the standard Istio tutorial.
See install notes.
Full tutorial instructions or the interactive way (using Katacoda).
These ones are used for Kiali testing: kiali-test-mesh.
A fictional pet photo sharing app: Petsiogram.
A dummy football/soccer simulation with microservices: Mesh Arena.