WhatsApp can be used to make calls to other apps as well as send messages.

Good news for WhatsApp users. From WhatsApp, you can make audio-video calls with other app users as well as send messages. WhatsApp is soon going to launch inter-operable facilities to give access to other organizations' apps from their own apps.

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According to market analysts, WhatsApp is going to introduce access to other organizations' apps from its own app to meet the requirements of the European Union's Digital Markets Act (DMA). When this new facility is launched, users can communicate with other app users without stopping WhatsApp. The new facility will initially be launched only in European Union countries.

Incidentally, the European Union has enacted the Digital Markets Act to create a level playing field by reducing the monopoly of large corporations. According to the organization, all technology companies or platforms with 4.5 million users per month in European Union countries must comply with this law.
Source: News18.com