|ios apps (Photo credit: osde8info)|
That's more than four times as many as BBM, and it has the mobile operators increasingly worried, because it works like BBM – over data – but on any phone that can run the app, including phones running Android, Windows Phone, Nokia's Symbian and S40, BlackBerry OS and Apple's iOS.
To communicate with someone, you both have to have WhatsApp installed. (It will recognise your contacts who do have it from their phone number.) That's a potential market of many hundreds of millions of users, and although the company hasn't released any formal numbers, it's safe to say that it's already really big, and likely to become even more so." Read it on The Guardian