Tweetbot users who have Tweetbot for iOS installed will now be able to take full advantage of the new character limit once the app update has been installed. Tweetbot has not yet updated Tweetbot for Mac with support for the new feature, but an update should be coming soon.
Twitter started testing the new 280-character limit in late September before rolling it out globally yesterday. The updated character limit is available for all languages with the exception of Chinese, Japanese, and Korean, as those are not affected by what Twitter calls "cramming."
According to Twitter, during the testing period, most people with access to the 280 character limit continued to share tweets that featured under 140 characters, so the company does not believe the new limit will "substantially change" timelines for most users.
Right now, since the feature is new, there is an uptick in the number of people testing the 280-character limit, but Twitter believes that will die down within a couple of weeks.
Tweetbot can be downloaded from the App Store for $4.99. [Direct Link]
Update: Tweetbot for Mac has also been updated with support for the new 280-character limit.