skribbl - Word guessing based on drawing.
Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
LetsDraw.It - Guess and Draw, Drawing Battle, Pictionary, Copy picture - online drawing games where you can compare your skill with others.
Invision - Prototyping and collaboration for design teams
gartic.io - Draw, guess, and win!
Sketch - Professional digital design for Mac.