WhatsApp is a benchmark of all apps of recent history and is one of the most successful real time messaging apps that are available for all platforms. You can easily exchange messages between iPhone, Android, Windows Phone, BlackBerry and Nokia phones without paying for SMS. Before you start developing an app like that you first have to understand that WhatsApp is not just an app – it’s a service. Once you develop an app you have to maintain its intended functionality.
It may cost up to $100000 to $250,000 if it developed in India or somewhere like Phillippines. Cost to develop in the USA would be 5x than it in India.
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