Based on our record, Paintstorm seems to be more popular. It has been mentiond 1 time since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
If she wants to expand and more than just mimic traditional paints there are even more programs she might want to consider, the king of the "generalist" softwares is Photoshop, my personal choice, but there are valid alternatives out there, starting from the free and open source Krita, to cheap but solid programs like Clip Studio Paint (especially good for comics/manga, but it can also do other stuff), Paintstorm... Source: about 2 years ago
Krita - Krita is a professional FREE and open source painting program. It is made by artists that want to seaffordable art tools for everyone. Concept art. texture and matte painters, illustrations and comics.
Corel Painter - Corel Painter is media painting software.
Procreate - Procreate is the most powerful and intuitive digital illustration App available for iPad®.
Clip Studio Paint - The artist's software for drawing and painting.
Autodesk SketchBook - SketchBook drawing and painting software provides designers, architects, and concept artists the tools to sketch ideas quickly and create beautiful illustrations.
PaintTool SAI - Learn to draw in different ways.