According to WhatsApp CEO, Jan Koum, the firm still has several technical issues to overcome before it can successfully launch seamless voice calling. Koum noted issues like how the app doesn't have access to certain microphones on the smartphone to properly enable noise cancellation. Koum was speaking at Re/code's Code/ Mobile conference on Tuesday.
Koum also added that the WhatsApp development team is looking for ways to implement the voice calling service in poor data coverage areas, considering that many WhatsApp users in emerging markets are still on 2G networks.
He further added that WhatsApp has no plans of charging users in future, and is instead focused on growth with Facebook's financial support. The company, which in August crossed 600 million monthly active users, now aspires to cross 1 billion monthly active users within the next several years, said Koum.
"Before [the acquisition] we experimented with monetization, we tried to charge in some countries," Koum told Re/code's Liz Gannes at the conference. "We didn't have the long-term financial support of Facebook."
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Koum claimed that WhatsApp's voice calling feature wouldn't compete much with Facebook Messenger, which also offers free voice calling, as the latter is meant to be among Facebook friends, while its own service would be for the wider spectrum of mobile users expecting direct contact.
WhatsApp's acquisition by Facebook in February was recently approved by EU regulators. Facebook closed its acquisition with the final price tag rising an additional $3 billion to roughly $22 billion because of the increased value of Facebook's stock in recent months.