Well, Iconfactory contacted me last week to do a couple sketches (in Linea, of course!) to help promote their Back-to-School Sale!
The app is currently 50% off, so if you're on the fence, it's a great time to pick it up! [
link!]
It works on all the current models of iPads, but if you want the most out of it, be sure you have an Apple Pencil!
I personally use it as a digital sketchbook -- it's great for drafts, notes, and quick sketches. I really love the natural look of their pencil tools and having multiple paper types (black, kraft, white, grey, blue-print) and a nice variety of guides and templates makes it really useful for daily use!
(You'd think this was drawn on paper, but it's all Linea!)