EntropyOS

EntropyOS starts from your actual course material instead of a generic calendar: you import the PDFs, it analyzes every single exercise, and it builds a complete study system around what you concretely have to be able to do, adapting the plan and the spaced repetition as you work through it.

It is the most shipped thing I have made so far, live at entropyos.fr, and most of what I know about finishing software I learned by having to finish this one.