This is how it works: According to a report, Facebook's app for smartphones that use Android operating system has a feature that links Facebook to the 'Tor' app.

The app allows users to circumvent censorship and shield their privacy, the report added. 'Tor' software is free and Facebook users with Android smartphones can install a mobile Tor app called Orbot.

Now rap a button in the Facebook app and be automatically connected to Facebook through the "Tor" network. However, Apple users cannot link to 'Tor' as they are on iOS operating system.

According to Facebook, the 'tweak' has not been designed with China and Iran in concern. However, industry analysts see the 'anonymizer' feature as a tool to expand Facebook's reach even further and deeper among smartphone users.

'Tor' was created by United States Naval Research Laboratory as a way to protect secret data sent over the internet. Facebook currently has nearly 1.5 billion monthly active users.