One of the key factors in Apple’s iPod success was it’s convenient user interface for navigating through the huge music libraries stored inside the player. And this user interface might get even better soon – it seems that Apple plans to add audio navigation to the iPods.

One of the problems when searching for a particular song or changing playlists is that you have to look at the tiny screen when navigating to the right place. This is particularly troublesome if you forgot your glasses or can not shift your eyes from other things you are doing. Like crossing the street, jogging or driving and watching the road ahead.

Now Apple may have found solution for this problem - Audio navigation interface. In patent application made public today Apple describes such a system for automatic generation of audio navigation tags for your iPod.

The tags are generated from the metadata of your music or video files - the text information like author, song name and duration, film director or lead actor name, etc;- which comes with a song or video that you download from iTunes store. This text information is then converted using text-to-speech software into a small audio files - audio navigation tags. The iPod computing capabilities are too small to do a good text-to speech translation, so this operation is carried out on your Mac or PC.

Audio navigation tags then are attached to the songs or videos themselves and transferred to you iPod. When getting there, audio navigation tags can be stored with the songs themselves or transferred to a separate database and then synchronized with the navigation menu. The same audio information can be generated for user playlists and every song in the playlist.

So for example when an iPod user wants to play “In the air tonight” by Phil Collins he navigates to the song using his preferred path: “Menu”->”Music”->”Pop”->”Phil Collins”->”In the air tonight”->”Play”. However instead of having to look at the screen, all along the way he hears audio prompts advising him on the next navigation steps.

Now, audio navigation menus are used in various business applications for a long time and there’s not much to patent here. However the clever thing with this particular Apple’s patent seems to be the way they solved the dynamic synchronization problem for constantly changing metafiles of huge music collections stored on the iPod.

By dynamically generating audio tags in iTunes on your computer when song is downloaded or playlist is created and then synchronizing it with the iPod, Apple is able to make audio navigation as easy to use and update as current text navigation system.

And since no hardware and navigation control changes are necessary, audio navigation can be added to current iPods through simple software update.