I’ve ported some software to the iPhone and iPad. Here, you can find out how to build this software yourself, and exactly what I changed and why in each package.
If you’re simply interested in installing these programs, and not in building them from source, most of them are available from my Cydia repository, with the notable exception of TeX Live.
You’ll need the on-iPhone development environment to compile most (if not all) of these packages. If you install them via Cydia, you do not need the development environment.