I always find the need to explain this to people because I was asked why I haven't made one when I've the programming skill to do so. Pretty much our strategy is too simple for apps, it's just "Get more people on our site" and making an app would mean keeping people from our site, not to mention I'd have to make an app for iOS, Android, Windows Phone 8, Windows 8, and more, while our website just works everywhere (I mean shoot, you can check us out on Nintendo Wii, Wii U, DS, DSi, PSP, PS3 and XBox 360 at this point).

The only things I'm willing to develop for this site are widgets (like what we have for Windows, Mac and soon Android), web app installers (like we have for Chrome/Chrome OS and soon Firefox/Firefox OS) and the ability to install our site to your home screen (like on iOS, Android, Windows 8, and Internet Explorer 9 or higher).

To any artists considering making an app to distribute or share your music, don't do it, it's a bad idea.
It's costly, will only work for a limited audience, creates a barrier to checking out your content and won't provide enough value for your fans to keep installed for more than a few minutes.

Just focus on having a website.

These days they do more than enough for what you want, you can even make them run offline provided that the viewer has an up to date browser.

(Source: XKCD.com)