I was just checking out a few websites about Linux news & came across this article
http://www.omgubuntu.co.uk/2015/04/s...lease-features , the article is focussed on Linux but a quick check of the Synfig Studio website there is also a version for Windows & Mac.
It says it is free but there is a donation button.
I hope this is of interest to content creators or those who would like to be.
Disclaimer. Please be careful about the websites you visit & what you download &/or instal.