With what help to design applications on Android?

Question

Android

Dear friends,
I'm far from an architect, I just "saw" applications for Android, but ...
One of my applications, the highest priority, the most important, has grown to an impressive size (meaning files and lines of code), and the documentation, except for Java, docks, I did not lead any. So far, I'm navigating in the code, but it's getting harder and harder to do it every time.
Therefore, I wanted to ask you, how and with what help do you compile documentation, draw diagrams, UML, and draw anything you like, just so as not to increase the next code-review in time, simply because there are no docks?
Any tools, perversions, tricks, books, videos, websites that will help me take the side of the force will do.
Thanks to!

Answer 1

somehow more and more the README.md file and google doc are not a panacea of ​​course, but it solves its task

Answer 2

stackoverflow.com/questions/28407913/generating-um...