Pencil2D - Pencil2D is an opensource animation/drawing software for Mac OS X, Windows, and Linux, based on old...
OpenToonz - OpenToonz is an animation program that is a free software version of Toonz, the animation software...
Adobe Animate - Adobe Animate is a Flash, vector animation software.
Invision - Prototyping and collaboration for design teams
ToonZoom Animate - ToonZoom Animate is a free web based animation app that works right in your browser!
Spine - Spine is 2D animation software designed specifically for software and game development.