You can send messages through WhatsApp in your browser or on your desktop, but you can only make calls on mobile. WhatsApp is designed for phones, so the web and desktop apps are intended to work with your mobile app, not replace it. It’s available for both Android and iPhone, and you can also download WhatsApp’s desktop app or access WhatsApp from your browser. WhatsApp is a popular phone app that sends messages over the internet instead of through SMS.