I have started implementing classical music mobile (web) apps based on this website.
Wikitude is a very nice way to see the MusicAtlas places. It is a real Augmented Reality (AR) application, available for iPhone, Android, Symbian, Bada, and more (see the list of officially supported devices).
To use this app, you must have Wikitude installed on you mobile device. Search for it in your app store, or go to the Wikitude site for more information.
When you add "MusicAtlas" as a "World" to Wikitude, you can see the classical music places in your neighbourhood: as a list, on a map, or superimposed on your camera view. Try it, it is quite spectacular!
If you want to try this app, then open the following link in your mobile phone, iPad, or other tablet PC:
The data for these apps come from the musicatlas, which contains thousands of places from all over Europe. New places are added all the time.
Let me know what you think of this, or if you have ideas for other mobile apps.