Well, there are some great plugins for android and iphone to update your WordPress specifically.
There are then many great plugins which send your posts off to facebook and twitter.... That's how I roll! I have several WP sites. Each has it's own twitter. My main blog auto posts to my personal FB page. The rest of my WP sites each go to a fan page.
Sound like it would work for you?
There are many plugins to do this, I suggest you do some research and find the ones that suit your needs....
I personally use:
http://wordpress.org/extend/plugins/simple-facebook-connect/
http://wordpress.org/extend/plugins/simple-twitter-connect/
Which also add many other useful features I like, I've also heard great things about
http://wordpress.org/extend/plugins/social/