The Netherlands has the highest usage of Whatsapp per capita. Literally everyone with a smartphone has Whatsapp. I'm currently in 11 active group chats and it's my main method of communication: That's 5.6k sent messages and 46k received in just under a year. About 130 per day, and I'm not even above average among my peers. I don't text or call people. Sometimes I mail, sometimes I get a message on Facebook but that's about it, the rest is all Whatsapp.It is.
The Dutch are weird, though. I had this app for a while that was supposed to help people learn English. It would pair you with someone from somewhere else in the world and you'd go off on scavenger hunts. Like, you'd have to take a picture of a bus in your neighborhood, they'd have to take a picture of a bus in their neighborhood. 90% of the people on that app are Dutch.