Can I set the default simulator for new projects in Xcode 7.1 or latest?

Solution 1:

No need to delete simulators!

1. Product → Destination → Add Additional Simulators...

2. In the sidebar, select the simulator you want to hide

3. Uncheck "Show as run destination"

Edit: Updated for Xcode 10

Solution 2:

You can select the desired simulator via the Hardware > Device > [OS] menu (Xcode 9):

While unchecking "Show as run destination" hides the simulator, this will also change the default value.

Updated image for Xcode 11.5

Solution 3:

Xcode 9 UPDATE:

In Xcode 9, no need to delete simulators, and the way to turn them on/off is to go in Product/Destination/Add Additional Simulators... select the simulator you want to turn off, then uncheck the box: 'Show as run destination'

Solution 4:

No. But...

• If you don't like the size of the 6s plus simulator, make it smaller with the simulator Window Scale menu.

• If you don't like the 6s plus simulator at all, delete it with the Xcode Window Devices menu.

Solution 5:

Xcode 12.5

In Xcode, go to Product -> Destination -> Choose Destination menu and selecting the device you'd like to be your default.
The original answer could be found in apple support forum here: Apple support forum,
In addition if you want to make the device smaller just hover over bottom right corner of the simulator and you will see the resize option