CamScanner is an app and cloud service that uses your smartphone's camera as a capable, on-the-go scanner. The software snaps, squares, crops, enhances, and PDFs single- or multi-page documents in seconds. Use the sharing features to post to your favorite cloud storage service (Drive, Dropbox) or send yourself an email with the PDF in tow.

It's a three step process:

First, find a relatively shadow-free, well-lit area in which to shoot your page(s).

Next, verify the automatic page "squaring." The software will automatically enhance the image.

Finally, choose a storage/email option, and you're done.

Take a look at the hastily-scanned example used in this demo.