Google Play Music Manager is an app that allows you to upload your favourite music to the cloud. Once you upload your music and listen to it from your tablet/smartphone.
You can access the Google Play Music Manager from Spotify and Rdio.
The Linux version of Google Play Music Manager is still beta, so errors may occur. To install Google Play Music on Ubuntu 13.04 Raring Ringtail, Ubuntu 12.10 Quantal Quetzal and Ubuntu 12.04 Precise Pangolin, do this:
Download Google Music Manager
For 32 bit systems:
$ wget dl.google.com/linux/direct/google-musicmanager-beta_current_i386.deb
For 64 bit systems:
$ wget dl.google.com/linux/direct/google-musicmanager-beta_current_amd64.deb
Install Google Music Manager:
$ sudo dpkg -i google-musicmanager-beta_current_*.deb
Fix the dependencies, if needed:
$ sudo apt-get -f install