2D Animation Softwares

Toon Boom Studio
https://www.toonboom.com/products/toon-boom-studio

Toon Boom Harmony
https://www.toonboom.com/products/harmony-stand-alone

Toon Boom Storyboard Pro
https://www.toonboom.com/products/storyboardpro

Toonz
https://opentoonz.github.io/e/index.html
http://www.toonz.com

KumoWorks – generates cloud image according to a silhouette you draw
https://opentoonz.github.io/e/download/kumoworks.html

TVPaint Animation – imitate traditional techniques Pen Brush, Gouache, Watercolour, Pencil, Felt-tip, Airbrush
http://www.tvpaint.com

Anime Studio Pro
http://anime.smithmicro.com

Retas Stylos HD – Revolutionary Engineering Total Animation System
http://www.celsys.co.jp/en/products/retas/index.html

CTP Pro – Cartoon Television Program
http://www.cratersoftware.com

Digicel Flipbook
http://www.digicel.net

Plastic Animation Paper
http://animationpaper.com

CreaToon
http://www.creatoon.com

Storyboard workflow tutorials using Krita
http://mango.blender.org/artwork/digital-open-source-storyboard-workflow

GraphicsGale – Animation graphics editor
http://www.humanbalance.net/gale/us/index.html