A convenient instant messaging service between smart phone
With WhatsApp you are able to send messages and carry messaging conversations through your phone to other users who have the WhatsApp app installed on their phone. WhatsApp is a paid app but it is very cheap, ranging from $0.99 to $1.99 a year depending on which phone you have. Paying for WhatsApp is a lot cheaper than any text message plan and it is unlimited. WhatsApp even allows you to send audio, picture, and video files to other WhatsApp users.
WhatsApp is very similar to BBM but gives you the ability to instant message to other phones. With BBM you are able to talk to other Blackberry users for free and it also gives you the ability to set up groups and have group conversations. WhatsApp is slowly catching up to BBM and creating more functions for the users, but currently they do not have the group chat function. I am sure in the future we will see this allowed for WhatsApp users. The cool thing about WhatsApp, which is also true about BBM, is the function to see when a message is received and when it is read. You are able to see what the phone receives your message and when the person reads you message giving you an easy confirmation that the message was successful in being sent.
Either method of instant messaging is easy and cost less than text messaging. I can see in the future the elimination of text message and a rise of popularity in instant messaging programs such as WhatsApp and BBM.