The Sympogical application is not available as a download. It has to be purchased from the Apple iTunes store.
A direct link to this is provided here.
However, if you wish to read my tutorial on the Quine McCluskey (QM) algorithm (for logic simplification) and Petrick's Method (used to resolve multiple permutations), you may freely download the tutorial below. This tutorial also tries to give a direct comparison to (logically equivalent) Karnaugh Maps.
This tutorial is provided as-is - if do you find any errors / suggestions, please let me know by sending an email to firstname.lastname@example.org