[sanju]

but developing countries still prefer to talk over chat.. if it comes to phone. young people in india use WhatApp as an alternative to email. so like we dont pay for email address.. no one will pay for WhatApp.. there are alternative like viber.. quite popular in india

[unsigner]

You don't pay for an email address, because thanks to email interoperability (not openness, which is a separate albeit related thing) a free email address is a decent substitute for a non-free email address. Viber is not the same kind of substitute for WhatsApp when all your friends/family are on WhatsApp. (I live in a market where everybody is on Viber btw, so the WhatsApp card is worthless even if they paid me $0.01 for each WhatsApp message sent)