<p><i>Open SSTP Client</i> is an open-sourced <a href='https://en.wikipedia.org/wiki/Secure_Socket_Tunneling_Protocol' target='_blank'>Secure Socket Tunneling Protocol</a>¹ (MS-SSTP) client for Android, developed for accessing to <a href='https://www.vpnazure.net/' target='_blank' rel='nofollow'>VPN Azure Cloud</a> (or <a href='https://www.softether.org/' target='_blank' rel='nofollow'>SoftEther VPN Server</a>). So no test with other servers is done.</p><p>For usage and more details, please visit the app’s project page.</p><p><br>¹ quoting from the Wikipedia article:</p><blockquote><i>Secure Socket Tunneling Protocol (SSTP) is a form of virtual private network (VPN) tunnel that provides a mechanism to transport PPP traffic through an SSL/TLS channel. SSL/TLS provides transport-level security with key negotiation, encryption and traffic integrity checking. The use of SSL/TLS over TCP port 443 allows SSTP to pass through virtually all firewalls and proxy servers except for authenticated web proxies.</i></blockquote>