We also held out on smart phones until our kids were 15 / 17 respectively. You held out even longer, so kudos for being able to do that. Our kids weren't mocked. They didn't feel left out. They didn't even complain because they had never had a smart phone so they literally had no idea what they were missing out on - which is nothing. They missed out on nothing.

In the end, we wanted a way to keep in touch with them and see where they were as they began driving and working. That's NOT a healthy reason to get a kid a smartphone, BTW. That's just a reflection of my fear and insecurity.