MultiVNC is a secure open-source VNC viewer that aims to be easy to use and fast. It includes the following features:

Support for most VNC encodings including Tight.
Encrypted VNC connections via AnonTLS or VeNCrypt.
Support for SSH-Tunnelling with password- and privkey-based authentication.
UltraVNC Repeater support.
Discovery of VNC servers advertising themselves via ZeroConf.
Bookmarking of connections.
Import and export of saved connections.
Virtual mouse button controls with haptic feedback.
Two-finger swipe gesture recognition.
A super fast touchpad mode for local use.
Hardware-accelerated OpenGL drawing and zooming.
Supports server framebuffer resize.
Copy&paste to and from Android.