Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
YouiDraw - Draw and Design Vector Graphics, Logo, Text, icon in the Cloud.
Drift - A messaging app that helps you grow your business.
Sketch - Professional digital design for Mac.
C++ - Has imperative, object-oriented and generic programming features, while also providing the facilities for low level memory manipulation