You can access music wirelessly on Android. It's called Google Music.
You upload all your songs onto Google Music. So, your songs are stored in the cloud.
You then configure the music app on your Android device, so, it syncs with your Google Music account.
So, you're able to get all your songs without needing internet. I think it also does offline, but, I'm not sure whether it takes any space.
I don't have an Android device, so, I can't give instructions on how to do this. A simple Google search should help though.
That's why I'm not concerned about the space limitations of Nexus 7 (if I were to get one, I would get 16GB though - 8GB is just too little, especially when you only receive a reported 5.7GB of the 8GB.)