Lottie - Lottie is an online platform that helps the users in editing and shipping their animations in a few clicks.
OpenToonz - OpenToonz is an animation program that is a free software version of Toonz, the animation software...
LottieLab - Create and edit Lottie animations.
Synfig Studio - Just another WordPress site
Animator - Animator is a small animation tool. Using Animator is really easy. Example : Drop file1.bmp.
Adobe Animate - Adobe Animate is a Flash, vector animation software.