Tbf kik is good because its anonymous chat on your phone.
Whatsapp is what you use for mates rather than texting/phoning them and using up minutes/texts.
Instagram is lol. Forget that
Facebook is useful again for group chats and to see how people are doing.
I've noticed that the people who act the happiest on Facebook are the ones who are the most depressed btw. By that I mean the ones always reiterating how happy they are.