While working on the android code. I find difficulty when i want to remove my changes or want to check what I have changed in the last 5-6 day.
While searching the Internet I find git tools as a good option for this purpose. Even once initialized the git there is not need of internet connection to check the diff with the original code.
Following are the links may be useful.
Android’s repo and git document http://source.android.com/source/version-control.html
A comprehensive docs on http://book.git-scm.com/3_comparing_commits_-_git_diff.html