I am new to Android world and I am really curious about how difficult it is to modify OS to add/remove applications. I am not talking about installing/removing apps from Android Market, but actually customizing OS to only include apps of my choice. That includes both standard/system apps as well as apps from Android Market. For example, what if I only wanted to have access to Google Voice application (and nothing else)? I guess in this custom version of the OS, I would not necessary have to remove the application, but could just somehow hide it from user.
In any case, any clues on the amount of effort/approach would be greatly appreciated.