This thread is getting old, but for those seeking an answer about where to start I think it always begins with a project idea.
Just learning to code "Hello World" is a bit boring and only gives some basics about how to use the tools and make a functioning app/program.
My suggestion is to get a project idea and figure out what it will take to make it work. For example; make an app that will record (sound or video), playback, save and get the file from the file system in the future for playback or modification.
Good luck, develop a passion for making the devices do your bidding and you will succeed!