WhatsApp - WhatsApp Messenger: More than 1 billion people in over 180 countries use WhatsApp to stay in touch with friends and family, anytime and anywhere.
FluffyChat - Open. Nonprofit. Cute ?
WhatsGreen Multi Messenger - Easy access to WhatsApp, Line, Telegram, FB Messenger and many others via the Chrome toolbar.
Signal - Fast, simple & secure messaging. Privacy that fits in your pocket.
WAToolkit - A set of useful and lightweight tools for WhatsApp™ Web client.
Molly (Signal fork) - Molly is an independent Signal fork for Android