The refresh includes a revamped interface that boasts a new sidebar on the left for easier navigation across columns.
The Windows version now matches the look and layout of TweetDeck's Web-based app.
Announced a few months ago, the new app programming interface cuts off support for TweetDeck, as well as a handful of third-party Twitter clients.
The newly revamped Web site offers up a cleaner design and moves virtually all of the commands a user needs to a left sidebar.
In March, Twitter announced it would focus efforts on TweetDeck's Web version. Facebook support, as well as versions for iPhone and Android, have disappeared.
Although the popular photo-sharing service turned off Twitter Card integration, users can still see Instagram photos embedded in tweets in the Twitter-owned TweetDeck client.
The application for power-users will cease to exist in three weeks, though the web app will continue as it is.
Twitter is laying to rest several versions of the power-user-friendly tool.
Twitter has re-engineered TweetDeck to work under the weight of trending topics, such as "#Debate," that would have previously crashed the application.
Personal browser apps will go dead after May so TweetDeck team can focus on Web-based versions instead.