UltraVNC Server, UltraVNC Viewer and UltraVNC SC | Official repository: https://github.com/ultravnc/UltraVNC

MultiVNC is a cross-platform Multicast-enabled VNC viewer based on LibVNCClient. The desktop client runs on Unix, Mac OS X and Windows. There also is an Android client.

VNC client for the reMarkable tablet allowing you to use the device as a second screen

WoVNC - http://www.wovnc.com

A simple VNC client with built-in SSH tunneling

It is now integrated in main UltraVNC sourcecode: https://github.com/ultravnc/UltraVNC

A multi-view VNC viewer for Linux, FreeBSD, macOS and others

Flutter RFB client(OpenGLES Texture) implementation based on libvncclient