Logs provide a way to understand how your tests are working and also a way to see critical information for specific clients at different iterations. You can console.log() or console.error() in your tests and log critical information for the clients.
You can easily find the logs for a particular device and see the logs at every iteration. Along with the user logs, system logs are for each iteration are also captured and displayed here.
Double-tap any of the logs to pretty-print the logs for that iteration.