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I don't own a Pro, but if you like simple controls, Sketchbook is available. it's free, doesn't have any of that freemium gunk (for the most part) and doesn't bombard you with 5 pages of settings.
I also like Sketchbook. Only $1.98 to unlock premium bundle. Gets 4.8 out of 5 stars with 215,000 ratings.
 
Over the past months I've been working on two CAD drawing jobs (I'm a retired architect).
I decided to use Concepts on my iPad, and enjoyed the whole experience - including a perfectly scaled printout.
So if you're into vector based drawing, Concepts is definitely worth a look.
 
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