Finally, my iphone 4 arrives, so I can test Page Scanner on it.   iPhone 4 has a great camera, and the raw image from camera is 1936x2592 (5,018,112 pixels); I have to scale it down before performing image editing, otherwise we'll have trouble when clicking done in the Tailor view:-( An update with the fix and other improvements is submitted.  Hopefully it will arrive soon. Except the issue, page scanner performs very well on iPhone 4. Image loading is quick and binarization is so fast and clean (hence the name "Fast Intelligence":-). I've bought quite a lot of scanner apps (about all you can find on appstore), and after going through them one by one, I have to admit I love page scanner's quality better! Now I am going to use iphone 4 as the de facto device for Page Scanner testing. Camera quality on iPhone 2G and iPhone 3G is too bad to do anything interesting, only time to time I used page scanner to capture password/serial number from one computer and type it on another computer. Page Scanner for iPhone 3GS definitely will be supported forever as it has a decent camera there,  however, I can't assure it to be as fast as iPhone 4. To have a more clear result, turn the source picture contrast to higher as shown below.  On iphone 2G/3G, doing so will lose some information; but with the camera on iPhone 4, all we lose is noise:-)