Welcome to WhatsApp! This is a multiplatform mobile phone messaging service that uses your phone's internet connection to chat with and call other WhatsApp users.
Before you download and install WhatsApp, make sure WhatsApp supports your phone type. Please check this here.
To download WhatsApp, visit this link on your phone. Once installed, ensure that the friends who you wish to message have WhatsApp installed on their phones. If they do not show up under the Favorites screen (Contacts tab on Android), carefully add their numbers to your phone contacts:
Need a more detailed explanation on adding friends? Read this article.
Now that this contact is visible in WhatsApp, select their name and click on it. You can message your friend and also send them media via the options in the chat screen. Happy chatting!
Provided you have an adequate data plan, it is free to send messages over WhatsApp. More details concerning cost are available here.
WhatsApp Support Team