Of the mass-market products, Apple's iMessage and FaceTime scored the highest, failing on only two requirements -- the availability of code for independent review and the out-of-band contact identity verification. This means they don't currently provide complete protection against sophisticated, targeted forms of surveillance, the EFF said.
Other widely used communication tools scored much worse, meeting only one or two of the seven requirements. This was the case of Google Hangouts, Facebook chat, Yahoo Messenger, Snapchat, WhatsApp, Viber, AIM, BlackBerry Messenger and several others. None of these products offer end-to-end encryption making communications through them susceptible to surveillance on the provider's side.
South African mobile social network Mxit and widely used Chinese instant messaging service QQ don't provide encryption at all, making them the least secure products of the 39 that were tested.
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