Manqueman

This changes somewhat with iOS 11, so the following relates to 10, sometimes 11.
Best scanner qua scanner (in my experience) is Adobe Scan(? -- the new standalone scanning app). By that I mean that it's the best at finding, scanning and cropping the scan. Tied with Adobe's app is the scanning feature in Notes in iOS 11.
Where both apps fail me: Work requires me to email multiple scans; emailing them individually is not an option. Can't do that with Notes. (Should add: "not that I've figured out and/or maybe it'll be a feature some day".) So to email multiple scans, I use GeniusScan -- which, of all the scanner apps I've used, is the only app that has that feature. I also copy the scans to my Box account; obviously, I can send multiple scans from a Mac from the Box folder.