You guys really should take what you learned building WhatsApp and start over.
Make it subscription based, with a low bar of entry ($10 or so per month), don't do ads, don't do data harvesting (unless required by law enforcement) and/or "science" (for profit), guarantee freedom of speech (as long as said speech is protected by law, ofcourse) -- in other words: don't become Zuck -- and you will outcompete Facebook come 2025.
There is a small handful of things will pay more than $10/month for: my mortgage, car, and utilities. We cancelled Amazon prime when it hit that, and will cancel Netflix when it hits that. I will not pay for text messaging; I'll happily continue using Android messaging instead.
Make it subscription based, with a low bar of entry ($10 or so per month), don't do ads, don't do data harvesting (unless required by law enforcement) and/or "science" (for profit), guarantee freedom of speech (as long as said speech is protected by law, ofcourse) -- in other words: don't become Zuck -- and you will outcompete Facebook come 2025.