I figured out a cool effect with the new clipping mask feature in flipaclip

Imagine this but it’s a thought bubble with Peyton in it

What feature?

If you draw something on a layer then enable clipping mask on that layer, it'll turn invisible

Then by drawing on the layer below it you can slowly reveal the layer you enabled clipping mask on.

Alternatively, there's alpha lock, which when enabled on a layer only lets you draw over pre-existing drawings on that layer

These were added in the latest update

Ok

how i do that is just draw what i want to draw, then erase all of it, then most of it, then some of it, then none