My older kids who are out of the house (early 20s) are android users. My wife is an an iPhone user, so it's a mixed bag at our house.
I just pulled up the usage report on my phone plan. My 18 year old HS senior has sent zero text messages this month. My 15 year old HS freshman has sent 31 text messages.
So far this month, I've sent 311 texts. My wife is at 680. The teenagers are on their phones 10X the time the adults are, but they're not sending any text messages. It's all going through snapchat.