Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
Social Fixer - Social Fixer for Facebook plugs into your browser and improves the existing Facebook.com web site.
WhatsApp Desktop - WhatsApp, now on your desktop
F.B. Purity - F.B. Purity is a browser extension / add-on that lets you clean up and customize Facebook.
Wafer Messenger - Endless Creativity, Limitless Reach.
SpaceHey - SpaceHey is a retro social network focused on privacy and customizability. It's a friendly place to have fun, meet friends, and be creative. Join for free!