I tried WhatsApp, then stopped using it when it became painfully apparent that unless all my contacts use WhatsApp, it will never be a good experience for me. I

I tried WhatsApp, then stopped using it when it became painfully apparent that unless all my contacts use WhatsApp, it will never be a good experience for me. I don't want fragmented messaging on my phone. Not only that, but SMS is very cheap. In Australia at least, most mobile plans come with unlimited, or more than enough SMS messages included in the plan to satisfy most people. I send a lot of text messages and it never makes any dent on my monthly bill. What I'm getting at is, I'm puzzled why the app is worth 19 billion.