README

An attempt to create a userland VPN feature for Android ICS 4.x devices that transparent routes all traffic through Tor without requiring root.

About ICS VPN Client API

VPN client API

Developers can now build or extend their own VPN solutions on the platform using a new VPN API and underlying secure credential storage. With user permission, applications can configure addresses and routing rules, process outgoing and incoming packets, and establish secure tunnels to a remote server. Enterprises can also take advantage of a standard VPN client built into the platform that provides access to L2TP and IPSec protocols.

More here: http://developer.android.com/reference/android/net/VpnService.html