That can't be true. I think *most* smartphone users are on Whatsapp. Even my 60 y.o. sister, my 55 y.o. brother, my 22 y.o. niece, my 19 y.o. nephew and my 18 y.o. son are on Whatspp. I suspect either a sync problem or (gasp!) almost all your contacts are still using dumbphones.