Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
Spine - Spine is 2D animation software designed specifically for software and game development.
Sketch - Professional digital design for Mac.
Synfig Studio - Just another WordPress site
Invision - Prototyping and collaboration for design teams
AnimeEffects - AnimeEffects is a 2D keyframe animation tool based on deformation of polygon meshes.