OS X: Any PDF to Kindle format converter to read technical material on Amazon Kindle? I like to read course material on Kindle. I merge all lecture slides with Automator and then send them to my Kindle email. Earlier, I have used Readle's Documents app (a spinoff of PDF Expert) where I had a search. If no OCR, then DjVU Reader in OS X to PDF and then ABBYY's FineReader Express to add OCR. Kindle has one failure with this: it cannot search despite the OCR of the PDF. It needs to be in a correct format: PDF is not a correct format but some Kindle's own format. 


  So does there exist any app in OS X to make material such as lecture slides suitable for reading in Kindle? Lecture slides are technical containing mathematical formulae.


It requires many steps already over OS X with Automator, DjVU Reader, ABBYY -- to make searchable in one way. I am trying to find an easy way with Kindle and Apple OS X.
Calibre is commonly used to convert ebooks (including PDF) from one format to another.  There is no guarantee that it does exactly what you want, but try it with your PDFs.