Psiphon is a free and open-source Internet censorship circumvention tool

Where other VPNs can’t connect, Psiphon <https://psiphon.ca/>
will find a way.

>From social media, to games, or VOIP, Psiphon is designed to
help you access the online content and services that you love,
even if they are blocked where you are.

Psiphon is a free and open-source Internet censorship 
circumvention tool that uses a combination of secure 
communication and obfuscation technologies (VPN, SSH, 
and HTTP Proxy). Psiphon is a centrally managed and 
geographically diverse network of thousands of proxy 
servers, using a performance-oriented, single- and 
multi-hop architecture.

Psiphon is specifically designed to support users in 
countries considered to be "enemies of the Internet". 
The codebase is developed and maintained by Psiphon, Inc., 
which operates systems and technologies designed to assist 
Internet users to securely bypass the content-filtering 
systems used by governments to impose censorship of the 
Internet.

Psiphon operates a secure network of constantly changing 
servers, and employ a variety of blocking-resilient protocols,
all with the end goal of getting you access to the open internet.

Source Repositories
These are the repos that will likely be of primary interest:

Cross-platform "tunnel core" client engine and libraries
https://github.com/Psiphon-Labs/psiphon-tunnel-core
	
Android app
https://github.com/Psiphon-Inc/psiphon-android

iOS VPN app
https://github.com/Psiphon-Inc/psiphon-ios-vpn

Windows application
https://github.com/Psiphon-Inc/psiphon-windows

All public repositories can be found at 
https://github.com/psiphon-inc/psiphon 
and https://github.com/Psiphon-Labs.