Well, even if this isn’t a general iPhone/Mac forum, but a Scrivener forum, here’s what you can do:
- Connect your iOS device to your Mac via Lightning to usb cable.
- On your Mac, run quicktime.
- Select File-New Movie Recording
- Click the down arrow next to the record button and select your iOS device.
- the screen of the iOS device will appear on your Mac.
I think you may need at least Yosemite to do this.
This just mirrors the screen, you can’t control the iOS device from the Mac. Also some apps, like Netflix may not appear on the Mac screen.