This project contains only the leptonica and tesseract-ocr libraries compiled for iOS.
There is no support for armv6, so it won't work with iPhone 1st Gen and iPhone 3G.
You might want to use this tesseract-ios to include Tesseract in your iOS project. For a more advanced usage, you can use the raw library with regular C++ code.
Don't forget to rename your implementation classes with .mm instead of .m as it uses C++ code.
Follow this blog post for more informations.