How I Use It
Coming from a digital arts background, many of these "sketchbook" apps over the same experience, however this one hits the nail on the head from a learning standpoint.
Used in many of my fine arts studio classes as an alternative to regular sketchbook assignments, students that were interested, downloaded the app and created their weekly sketches on their mobile devices. Images were saved and then turned in digitally through email or social media post.
There is a bit of a digital learning curve, and those users who may not be familiar with the universal "image editing" vocabulary, may need to be brought up to speed. However, SketchBook Pro does a great job at not overwhelming the user with too many bells and whistles, and puts the important tools right at the palm of the users hand.
I have to say that SketchBook Pro would be my digital sketchbook app of choice for my classes. The user experience is awesome, and with little time dedicated to app demonstration and overview, students are drawing in no time.
The only downfall, for ANY digital drawing program that is, that can the absence of a phyiscal writing tool can somewhat alter the drawing experience. While there is no substitution for the "old school" methods, a stylus can only improve the users experience with this app.