well, there are a few things:
- using the app to take photos (in a scan sort of mode, where it trims it to be at right angles), really quick and easy, no matter where i am.
- remote access - i can view all of my documents where ever i am.
- easy & sophisticated search. I have my documents assigned to people (me, wife, child, etc). I also assigned them to things like payslips, tax, shares, legal documents, education docs, receipts, etc. it also helps to automatically tag them to some degree of accuracy
- Automatic dating, it is quite good at picking out the date of the document, as seperate to the upload date. and it is easily updatable if it is wrong
- OCR - the documents content is searchable!
- Ease of tax time. I have some financial year views that make it really easy for me to do my tax (Australia), and i dont need to go hunting for paper that has faded in the heat and is no longer legible.
- folders - the documents are placed in a folder structure of your choosing. if you change the details in the document meta-data, it will move it to the correct place.
so, whilst a folder structure would work. this is SOOO much easier, and provides much more functionality as it is not just storage. it also has WAF!