I just noticed that there is an iPhone application for writing and organizing blog from WordPress(both .com and .org for self-hosted)
So I’ve just download it via appstore and begin to write my first post with it.
This is very useful!
PS. It would be nice if I can use Emoji here 
yep, quite useful indeed.
I tried it when it first came out in mid 2008
but that time I had problem with title in multilingual so I stopped using it. there were also few errors when trying when saving long post. I guess they have it fixed by now.
iphone.wordpress.org
mac.