You're right that a multi-word `SIM_DEVICE` value must be single-quoted for it to ultimately be accepted (by `defaults write`, in the `set_simulator_device` script)--but it looks like `defaults write` actually requires both double- _and_ single-quotes (like `"'iPhone (Retina 4-inch)'"), which is a little weird; I feel like the expectation is that you can usually get away with simply using one pair of quotes.

So, I feel like a better fix might be to have `set_simulator_device` single-quote the argument to `defaults write`:

```sh
defaults write com.apple.iphonesimulator SimulateDevice "'$DEVICE'"
```

Thoughts?