Rakuten Viber Messenger

Rakuten Viber Messenger is a popular voice-over-IP (VoIP) and instant messaging application used by over a billion users worldwide. Developed originally by Viber Media and subsequently acquired by the Rakuten Group, the application is designed to consolidate high-definition voice calling, video conferencing, secure messaging, community hosting, and e-commerce-adjacent features into a unified client.

Viber includes internal peer-to-peer VoIP and external telecom bridging. For users communicating within the Viber network, the app enforces end-to-end encryption by default across all standard voice calls, video chats, and textual threads. This cryptographic implementation ensures that no intermediary servers—including Rakuten’s internal systems—can intercept or read private messages.

Conversely, for external communications, Viber features "Viber Out". This software gateway bridges the digital internet protocol layer with standard public switched telephone networks (PSTN), enabling users to place calls directly to traditional landlines or mobile numbers globally at low rates.

The platform also includes social features. Viber supports group chats for up to 250 participants and public channels or communities that allow organizations to engage with unlimited audiences. These public channels are monetized through advertising networks, brand partnerships, and in-app sticker purchases, presenting a distinct contrast to purely utility-based messengers.

Because the app is supported by advertising and transactional services, it collects certain user data points, including location variables, unique device IDs, and contact address books, which are encrypted during transit to secure servers.

This data collection supports Viber's caller ID system, which cross-references incoming calls with user-reported spam reports to identify robocallers and spammers.