Thanks to one of those promotional emails I discovered one app that was too true to be real. Supported by the MacHeist team, it did not only do something that no other app does, but did it in a beautiful way. Something like being part of a Delicious Generation of iPhone apps.
Once you select a track and play it, a synchronised swing will start marking the tempo and scrolling automatically the sheet music for you. A progress bar on the top represents the length of the tune and you can also dig into the data included, a link to the Wikipedia article, find it in iTunes, share it on social sites and via email and also to delete it from Etude.
The mechanics are this simple. The initial screen is a library with all the booklet cover of your tracks resting on a wooden shelf. Yes, again the visual metaphor of the physical objects resting on a piece of furniture that we saw first on the Mac with Delicious Library, then on the iPhone with Classic, and more recently with Apple's iBooks for the iPad.
Etude also includes a "zoom in" animation of the booklet opening, rather similar to iBooks. This makes me realise that I could be in front of the iBooks for classical music. Anyone taking piano lessons should be impressed already, but the actual music playback is not as satisfactory as real purists would like. I felt that the tune and the automatic scroll are not perfectly aligned, and what is worse, it's can't be adjusted. The result, sometimes, is choppy. If you don't take Etude as a serious learning app, it is acceptable, but you can't just expect an in-depth learning power tool.