I’d like to suggest genius scan for DavidE as an app to try out. Great edge detection.
What (who?) is “DavidE”?
Presumably @MacSparky, who has at times asked for users to flag scanner apps they like?
Possibly, but I’ve learned the hard way here that what words appear to say are not always what they were intended to say, LOL.
I just use Apple Notes to scan documents now. You can save the scan as a pdf if you want to keep it permanently in your file system.
The EagleFiler app running on my 2018 MacBook Pro knows how to scan documents on my iPhone XS. No installation or setup was required for the phone. (It uses the built-in macOS Continuity feature.)
Not sure what criteria you have in mind. But Prizmo has been working very well for me.
Adobe Scan does a great job with both documents and business cards.
I previously tried—and love— Genius Scan.
Up until I realized that OneDrive comes with this “Microsoft Lens” (also available as separate app) that has even better edge detection.
I keep both of them installed on my phone. Genius Scan has good edge detection and better UX (auto detect and capture, document manager). OneDrive with Ms Lens has better edge detection, and integration with OneDrive.