Spotify has been busy improving its software of late, updating the way it works on Windows and Mac PCs, but more importantly for us, how it operates on Apple's iPhone.Yes, a new version of Spotify for the iPhone is now available. It doesn't radically change how it works on your smartphone, just makes things work a little better all round. According to Spotify, the new app has a much faster start up speed, with the Spotify app now loading six times faster than previously. Also, Spotify will not start playing after you hangup a call if you have removed your headphones during the call.In addition to that, there are now retina display-friendly graphics for the iPhone 4 and iPod Touch 4G, the option to attach a message when sharing to your Spotify friends and improvements in how Spotify reloads your position after a restart. You no longer have to wait until you get online or tap to cancel before you can use Spotify.Finally, there are some stability fixes related to log out, opening links, changing songs, login, and more. Like we said, nothing radical, just a general all-round improvement, so it's well worth spending a few seconds downloading the update if you use Spotify on the go.