Write and send messages to your friends and contacts from your iPhone.
Though you only get a few extra useful features, WhatsApp Messenger is an excellent choice for sending free texts across platforms, even internationally.
CNET's Luke Westaway explains how WhatsApp has quietly become the most important app on his phone, and a better social tool than Facebook or Twitter.
The Facebook-owned messaging service retains its position as one of the largest platforms around, according to numbers from WhatsApp.
The new feature could help WhatsApp better compete with the likes of Skype and Viber, which offer both chatting and voice calling.
WhatsApp's cofounder claims the company is focused on promising the best experience for users, even to the detriment of interoperability with other services.
It's a big round number and all, but in the world of mobile messaging BBM remains one of the smaller players.
WhatsApp users can now message each other using their computers, in addition to using the mobile app.
The popular messaging app appears to have switched on its promised voice calling feature, with some users reporting the functionality appearing in the latest app build.
Tired of only being able to access your WhatsApp conversations on your phone? Start using WhatsApp Web.
The popular chat service makes its way to desktop and laptop computers, but those who use it through an iPhone will have to wait.