Neater, picking a font

I am designing http://neater.co and I am playing with different fonts.
You can see the big picture here: http://cl.ly/image/3H3q471g0e1I

Before commenting I invite you to check out the designs on an iPhone/iPod Touch. I have made a web page for each mockup:

http://neater.co/fonts/1.html
http://neater.co/fonts/2.html
http://neater.co/fonts/3.html
http://neater.co/fonts/4.html
http://neater.co/fonts/5.html
http://neater.co/fonts/6.html

I prefer feedback on readability and ease on eyes. Whatever is your opinion and I am interested in the why.

Thanks!