Sometimes I get no IOS simulator devices listed in Visual Studio. when I try to run it squawks no device selected. Other times they are all listed. Not sure what I am not doing or doing that I shouldn't! lol.
This looks roughly similar to Bug 38695. You might find that the Cycle 7 Beta version (available via the updater) behaves better, except for one small additional issue where the simulator list gets cleared if you close and reopen a solution (Bug 41086, which will be fixed in the next Beta).
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