I only see about 16 devices available in Firebase Test Lab and from Google I/O I got the impression that there were going to be more. There was specifically a question asked about this in one of the session Q/A. Are there more devices than the ones listed on the device selection screen and if so, how can they be accessed?
Currently we're using AWS which has several hundred supported devices including devices that are running on distinct networks and I was expecting something a bit more in that ballpark.
What you see in the console is everything that's available at this moment. It's definitely a priority for the Test Lab team to get more devices on board, but it's not exactly easy to do that at the scale required for the particular set of services that Test Lab provides.
You can also get a list of devices by using the gcloud command line:
gcloud firebase test android models list
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