Since this thread got necromancied I'll add that at school we've been using Blender. It has surprisingly good 2d animation capabilities. Before that I was using FireAlpaca but the problem with that is the lack of a timeline or a keyframe system

Continuing through this dangerous island. Lunar has been rouged. There is an annoying Toxic Body Rouge plaguing the tribe. Zipper has had a son with each of his mates. Willa's son is Firo and Reana's is Sirku. Reana has gained a Yellow gem. Ripple and Lena have a digging son named Rusty. We need some girls for this recent wave of boys... Ina has died of hunger damage. Zipper, Willa and Reana have all died of old age.  The Trio has left behind another pair of Sons. Blue eyed Major and Basic boy Phantom. Angel and Elio have a gorgeous, Ram Horn Spotty girl. Little Rose will be a mate for Major. Fifi and Rayna have both died of starvation damage. Kai and Raven have a daughter who is a twin to her father. She is named Flower. Kai gains a Yellow Gem and a Pink Gem.