Whatsapp: Yeah, I use this a lot for communications. Here not having Whatsapp means basically no texting as no one I know of has used SMS in over a decade now.
When I was visiting Germany in 2019, I installed Whatsapp because it was clear that it was how groups and individuals messaged each other there. Here I find that Messenger provides the same function among groups and individuals, and I haven't used Whatsapp since I got back from Europe. Both free you from a single device which is what happens on SMS tied to a single phone number. Nonetheless many of my contacts prefer SMS, presumably since they are 1) older and 2) have my mobile phone number already.