Will make your test run in an emulated iPhone 12 Pro view. It means you can now use `click(delay: 0.5)` to emulate some long press or that `mobile_view=1` will be set automatically.
Usage:
```
it "works", mobile: true do
visit("/")
end
```
Note: `window-size=390,950` is different than native iPhone 12 Pro size, but due to minimum browser size and the automated browser alert at the top of the view, this was the best size I could find.