I want to make several pictures into 1 PDF, 1 image per page.

I got some cool mangas from a friend, and want to read them on the go on my iPod. It is jailbroken so I have a PDF reader. How can I make these all into one PDf files? I tried pasting into word but part of the page was clipped off, and I don’t want to have to use CMD and some program to merge them.