I have three questions: One for android and one for ipods

First question: How do I listen to music other than Pandora on an android, specifically an HTC one m8? Is there a way I can listen to the music on my itunes on my android?

Second question: How much GB do I need to comfortably fit 2500+ songs? I have a very large music collection and yes I need all 2500+ songs on my ipod. Just a quick peek at best buy it looks like I may need an iPod touch, but I prefer an iPod nano.

Third question: Is the iPod touch a cell phone as well? All I want is to listen to my music on the go and do not need all the bells and whistles of a smartphone and I really don't know how I feel about how large the iPod touch is compared to the iPod nano.

Thanks!