I am building an iPhone/iPad application to read pdf files and so far managed to download, open file, zoom in/out, bookmark etc. Since I am not an expert programmer, I was only able to do this after reading lots of blogs and questions on stackoverflow.
I have also included a search function and found the following site helpful in explaining the use of CGPDFScanner
http://www.random-ideas.net/posts/42
Now the mystery to solve is locating the text position in the pdf and highlight the results (exactly like in iBooks). Many people have already said pdf parsing is very complicated and I am hoping someone can share their code.
After two weeks of painful search I finally found this!
FastPdfKit