OpenToonz - OpenToonz is an animation program that is a free software version of Toonz, the animation software...
Free Texture Packer - Free Texture Packer is an open source tool that allows you to pack multiple images into one atlas for you games or sites.
Adobe Animate - Adobe Animate is a Flash, vector animation software.
Sprite Sheet Packer - Sprite Sheet Packer is online that you can easily use to pack sprite sheets, including data formats for CSS, LESS, and Phaser.
Pencil2D - Pencil2D is an opensource animation/drawing software for Mac OS X, Windows, and Linux, based on old...
Sprite Monkey - Small and fast but still full-featured sprite sheet editor.