After updating to OS X El Capitan 10.11 and updating to Xcode 7.0.1 I ran into some issues with the simulator.
At first the simulator would launch but I couldn't register/log in to the app because the ATS Key was needed. That was added, but now there is a different issue.
Whenever I try to launch the simulator, it appears in my dock, but it's inactive. It doesn't ever actually open and if I click on it's options, it shows that he simulator is not responding.
It had worked initially when I opened Xcode using sudo in terminal, but trying that again, I still am running into this issue. I've been looking everywhere online to find if anyone has had the same problem, and I've yet to find a solution.
Best Answer
I had the same problem on my 13in non-Retina MacBook Pro. I fixed it by going to my project, building and running the project, and when the Simulator.app opened, I pressed the "Stop" button.
This worked for me, but it must be a bug in Xcode 7.0.1 because just a few days ago my simulator was running fine.