I suspect that WP7 is largely an abandoned app platform.
Not that I've ever played it, but just out of curiosity I checked this out.
Current WP8 Version - 1.1.2
Current iOS Version - 1.1.2
Current Android Version - 1.1.2
My droid was non-rooted and I could FTP or SSH into a server, edit html, and so much more.
I've seen a few FTP Client apps for WP8, and I've even seen a FTP SERVER app complete with it's own virtual file manager.