1. Wentges you
All correspondence and contacts are vulnerable to espionage by both can monitor your Internet connection. Username whatsapp is a phone number, and password are automatically created when you sign up for the program, and is sent to the user's name in every time you use the program text is encrypted format, which means that anyone who can monitor your connection will be able to know.
Voice communication failure while showing the user to connect an ongoing process and it seems to him that the phone caller receives a call, at which time the application whatsapp does not appear on the other side of any signal incoming call, but teaches at a later time through the upper status bar, that he had missed calls on her.
3. Only for the rich
The application is available only on Android phones, because the parent company is targeting users of this kind of smart phones, and the number of users which exceeded the 700 million whatsapp them.