I'd be happy to stump up the £2.29 to unlock them, as the app is pretty good, but felt a little bombarded.
Anyway, nicely built app with a range of brushes that allow their colour, opacity and size to be set- using an odd slider system... these settings stay with the brush, so you don't have to reset when swapping between tools.
Undo is hidden under the screwdriver icon, so it's two taps to get to it, which is a bit poor for such a comonly used feature.
Pinch to zoom works without issue, no problem detecting actions as drawing strokes.Layers are available in the pro version, but I struggled through using opacity and an eraser.
Colours are presets in the basic version, with a better colour picker in the pro version.
Export is to jpg or png or psd, social media, other apps etc.
Today's sketch challenge was to draw a zebra, which I always think of as a cross horse, perhaps I should do some research next time.