Effectiveness

In testing Scan2PDF Mobile, I used several Windows Mobile devices including the HTC Touch Diamond and Samsung Epix.  I got better results from the Touch Diamond because its onboard camera has an auto focus feature which allowed me to focus on the text without having to move the smartphone back and forth.  The results you get will depend largely on the camera you have (and your lighting conditions -- the brighter the better), but Scan2PDF Mobile will work as long as your smartphone has at least a 1MP camera. 

I was surprised by the quality of the scanned documents.  While not perfect, the software performed much better than I expected.  Documents were clear and readable on my PC, and I was able to read every document that I "scanned" with Scan2PDF. 

Using the software's settings, you can create PDF files in the A4 format or the slightly smaller Letter format we're most used to in the United States.

I've attached one of the PDF files I created with the software so that you can see the result:

Amazon Receipt [PDF]

Performance

The software is quick and, at least on the devices with which I tested it, converted photos to PDF documents in a few seconds each time.  

My only complaint is that the software requires the use of your smartphone's camera software instead of having the photo taking capability built into the software itself.  This would be a nice touch, and speed things up a bit.

Conclusion

Scan2PDF Mobile is so incredibly useful that I've begun using it almost daily.  I'll scan in bills, business cards, recipes, receipts, magazine articles, ads -- all archived and ready to either be read later, saved or shared (I didn't send any copies of my bills to anyone, but if you're interested in paying any of them, just let me know). 

Although the interface is basic, and I would like the "scanning" to be done in the application itself rather than the phone's camera software, Scan2PDF Mobile is a fantastic and endlessly useful program for most smartphone users.