Viber is a very well-known and highly used cross-platform instant messaging and Voice over IP (VoIP) application which is available for free download. It was first developed and popularized by an Israeli company called Viber Media. Not just instant messaging, users can also send and exchange images, video and audio media messages in real time. Viber is available to use over WiFi or 3G and it's sound quality is just as good as a regular call.
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Viber Outage Reports from last 24 hours