This article will give you a simple tip how to backup your codes in a cloud and use version control at the same time and completely for free. This option uses Git that is included in Eclipse bundled with Android Development Tools and Dropbox.

Code backup

You are probably doing this already. One of the possibilities is to use a cloud storage service. You can use Google Drive or Dropbox, which is my favourite. If you don't have a Dropbox account, get one (this is a referral link. If you use it, we both get extra 500MB of space to use) and install Dropbox.

You can simply put your workspace or your project directory inside Dropbox (symbolic links work too).  Each change is automatically synced with Dropbox server. As a bonus you have your codes available from anywhere.