My oldest (12) likes to draw, and is currently using a free version of ibisPaint on her phone.

What's a good upgrade to that?

I'd love to get her a tablet + pencil, but I'm not quite ready to shove an overpriced Apple thing in her hands. But I also want to encourage her and not give her crappy tools/software.

@pixelambacht I’ve seen some drawing apps appear as deals in Humble Bundle: https://www.humblebundle.com/software. It might be worth keeping an eye out.
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@Stuarthazley That's a great suggestion! Thanks!