Example use case: You're in a hotel and want to connect to the WiFi so instead of looking at their sign and typing in the password by hand, you just take a photo and launch the app and then paste the password where needed.
Would also be good for power users with apps like Launch Center and pythonista.
Ocropus is really slow, but does seem to work better than tesseract out of the box. It's still quite bad with camera-captured images and IIRC doesn't give you any hooks to improve the results.
I couldn't find any other viable options when I was looking about six months ago.
I want an SDK that gives me an easy way to train the OCR engine. That means being able to view the images which performed badly, with text bounding boxes and the OCRed text overlaid that allow me to manually correct the results which it will then learn from. And, perhaps most importantly, good defaults for the common cases of document scans & camera captures.
btw, I'm kind of just brainstorming now.