Hi Chris,
The 8 MP camera on the 4S and 5 is definitely a fair bit better. As for your
lack of success with Prizmo, have you ever had a sighted person try this? It
would tell you very quickly whether the problem is the camera or the fact
that the picture you take is not focused enough, too blurry
Anytime you can improve the camera you will improve the results of your scans.
I have an iPhone 4 and use Text Grabber and get good results. Note: I didn't
say perfect results but you can edit your document to correct typing errors. I
got Text Grabber one day when it was free so I figured
