Facebook: 1.23 billion monthly active users via Facebook
YouTube over 1 billion monthly unique users via YouTube
Twitter: 241 million monthly active users via re/code
Qzone: 599 million monthly active users via TechCrunch
Sina Weibo: over 500 million users via The Next Web
Renren: over 170 million users via iResearch iUser Tracker
VK: over 230 million registered accounts via VK
LinkedIn: 259 million active users via LinkedIn
Google Plus: 343 million monthly active users via GlobalWebIndex
Tumblr: 181 million blogs via Tumblr
Instagram: 200 million users via Instagram
Vine: 40 million registered users via Vine
Tagged: 20 million unique monthly users via Tagged
Foursquare: 45 million users via TechCrunch
Pinterest: 70 million users via The Next Web
Reddit: 114 million monthly unique visitors via Reddit
WhatsApp: 450 million users via Facebook
SnapChat:  ???? via TechCrunch

via The Realtime Report

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