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By using Dropbox instead of an external hard drive, you can take everything that matters, like your music collection or password files, with you without the need to carry extra weight. After installation on your computer, any file you save to your Dropbox will automatically save to all your computers, you iPhone and iPad.

To sync your iTunes with Dropbox just follow these three steps:

1. Move your iTunes folder to your Dropbox folder. Depending on your iTunes library and internet connection this can take a long time.
2. Launch iTunes while holding the option key (shift on Windows).
3. Click choose library and choose your iTunes library folder in your Dropbox.