Best practice for making wordpress blog accessible via mobile?

Can anyone direct me on the best way to make my wordpress blog accessible via mobile devices? I’ve looked at the plugins and that seems like it’s one way to go. There seems to be issues with SEO, although they may have been resolved.

Are there methods of using themes for dealing with this? I don’t want my blog to be mobile only.

What have you found to be the best way of handling this?