Privacy International is particularly concerned that suspicion of membership of the Gülen movement is based on the use of encryption, specifically a freely available messaging service called Bylock which the government claims is the communication tool of choice for Gülen supporters and was used to organise the coup. There is very little information about Bylock; it is not widely known among security experts or outside of Turkey, it is no longer available from any app store and its origins and developer are something of a mystery.
Privacy International @ Medium » Encryption At The Centre Of Mass Arrests: One Year On From Turkey’s Failed Coup »