It’s universally acknowledged that anyone sitting next to a person who is using a device — phone, laptop, whatever — is allowed to spy. If you’re tapping away on something, expect to have your emails and texts peered at by your seatmates. That’s the price we all pay for having private conversations on a public platform. But it’s also a rule that you’re not supposed to make the spying obvious. You’re not supposed to lean over, point to the other person’s screen, and say, “Why don’t you count to 10 before you send that text?” or “I think you misspelled chlamydia.”