@anywhere from twitter is a great Javascript only solution. But it seems I couldn't integrate bitly api with @anywhere tweetbox.
Tweetbox of @anywhere can have default strings to show up in textarea where you can tweet. I am using bitly api to shorten url right now, but I can't figure out how to pass that shortened url to tweetbox.
I've solve my problem.
I call bitly api by using jQuery ajax method within the method I call @anywhere api so that I can use the short url.