Did resizable simulators go away in Xcode 7?

Yes, they were intentionally removed.

Can you provide an explanation as to why their were intentionally removed?

They were extremely useful, and seem like they would be more useful going forward with the advent of Split View and Slide Over.

Resizable Simulators are really useful for testing apps on the iPad mini screen size, and right now there are no other way of testing apps on the Mini Retina interface.

jeremyhu can you find from your Apple bosses how would developers test for iPad min on simulator?

There's nothing about the resizable simulator support that enabled iPad Mini support. We've just never shipped iPad Mini simdevicetype profiles becuase there is no need for them. For the iPad Mini, you should just use the iPad 2. For the iPad Mini Retina, you should just use the iPad Air.

I do not have Xcode 7 installed but I had a similar issue on Xcode 6.4 and was able to solve it by going to Window > Devices and manually adding each device that I needed using the ➕ button at the bottom.

How do we test at iPad Pro resolution without a resizeable ipad?

thanks in advance for your answer

-tim

Select "iPad Pro" from the menu 😉 It's available in Xcode 7.0 GM and 7.1 beta1.

The resizable simulators were useful when testing what happens when a device changes the size class of the running app (for example when entering Split View), other than using a physical device how would I go about testing that now?

Test with split view in the appropriate simulated device.

I didn't see the iPad Pro option in Xcode 7.0b5 or 7.0, but I do see it in Xcode 7.1b3.