Users of the popular messenger that use iOS and Android devices will get the voice communication feature first, but the Windows Phone and the BlackBerry versions of the app will follow shortly. However, it is yet unclear if calls in WhatsApp will be free, like in Viber, or with some kind of monthly subscription.
WhatsApp experienced some serious issues with its servers a couple of days ago, which led to a long outage, but everything is back to normal now. However, many users waved "Goodbye!" to WhatsApp and switched to rival messengers, such as Telegram.
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