As we've written previously it's important to us to provide methods for people to use our services securely – particularly if they lack reliable methods to do so.
This is why in the last two years we built the Facebook onion site and onion-mobile site, helped standardize the ".onion" domain name, and implemented Tor connectivity for our Android mobile app by enabling connections through Orbot.
Over this period the number of people who access Facebook over Tor has increased. In June 2015, over a typical 30 day period, about 525,000 people would access Facebook over Tor e.g.: by using Tor Browser to access www.facebook.com or the Facebook Onion site, or by using Orbot on Android. This number has grown – roughly linearly – and this month, for the first time, we saw this "30 day" figure exceed 1 million people.
This growth is a reflection of the choices that people make to use Facebook over Tor, and the value that it provides them. We hope they will continue to provide feedback and help us keep improving.
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