You are right; everyone uses messengers. There are so many of them: Skype, FB messenger, Whatsapp, Viber, Telegram, WeChat, Snapchat, Slack. Each of them has it's own fans and haters, each user installs what works for him or was recommended by relatives.

SMS messages seem outdated, but in fact, it is the most popular and reliable communication channel in the world. It does not matter what messenger app you prefer; you always have a phone number and thus can receive a message.