The list of free apps that are similar to WhatsApp includes Viber, KakaoTalk Messenger, LiveProfile and Skype. All of the listed apps are available on iOS and Android devices. They are also compatible with devices such as the Blackberry smartphone and Windows Phone.
Unlike WhatsApp, which requires a one-time $0.99 fee, many downloadable apps are free of charge to the user. Many free apps have features analogous to WhatsApp, such as Viber, which is able to scan a user's contact list and determine whether any of them also use Viber to enable communication between accounts. Although Skype requires its users to approve their contacts before being able to send messages, it also provides free calls and video chat functionality.