The developers of WhatsApp have recently upgraded the app to allow voice calls. the sound quality of these calls (made over an internet data connection) are extremely impressive, and may offer themselves for broadcast purposes.
According to Wikipedia, in January 2015, WhatsApp was the most globally popular messaging app with more than 600 million active users. In April 2015, WhatsApp reached 800 million active users.
The fact that WhatsApp is particularly popular for younger smartphone users may offer unique opportunities to reach new audiences. It could also lead to much cheaper mobile bills for individuals and businesses alike.
WhatsApp Inc., based in Mountain View, California, was acquired by Facebook on February 19, 2014, for approx. US$22 billion
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