Tall Tweets can help you post messages on Twitter that are longer than 140 characters. The tool will slice and publish your “long tweet” into smaller chunks of 140 characters or less and thus your Twitter followers will be able to read your entire tweet in their timeline itself.
The tweets are numbered and are sent in a reverse arrangement such that they can be read from top-to-down inside any Twitter client.
To get started, sign-in with your Twitter account, compose a tweet and hit publish. If there are hyperlinks in your tweet, they’ll be shortened using bit.ly. The app uses OAuth and therefore you won’t have to share your account credentials anywhere. [source]