Gravity!

TweetDeck aims to evolve the existing functionality of Twitter by taking an abundance of information i.e twitter feeds, and breaking it down into more manageable bite sized pieces. From a poster's point of view, it supports shortening URLs by a couple of different services, posting and hosting images at different sites, and scheduling tweets to be posted even if you're offline.

Tweetbot is a full-featured Twitter client with a lot of personality. Whether it’s the meticulously-crafted interface, sounds & animation, or features like multiple timelines & smart gestures, there’s a lot to love about Tweetbot.

Tired of seeing ads and promotions in your timeline, being disrupted by tweets from bots and people you don't like, or just want a pure Twitter experience back like the good old days? Try Twidere for Twitter!

Gwibber is an open source microblogging client for GNOME developed with Python and GTK. It brings the most popular social networking web services to your desktop and gives you the ability to control how you communicate.

Alternion is a social hub and communication center that enables you to combine and manage all your social web and email in one place.

Echofon: social apps for Twitter and Facebook.

Socialite is a revolutionary social application that keeps all your social networks in one convenient place!Socialite makes it easy to stay in touch with the social networks and services that matter to you.

Tweetdeckr is an open source TweetDeck replacement client.

Twicca is a Twitter client for Android that is simply awesome.

“mybucketz” is your social media unified. The application allows you to connect to Tumblr, Instagram, Twitter and/or your favorite RSS feeds, bringing all of your feeds into one central location. Not only does it provide a one-stop shop for these social networks, it allows you to group friends/followings across these networks into individual "buckets”. A bucket can be anything from one person you know, to a group such as family or co-workers, or even just a description like sports. The buckets you create, your connected social network feeds, or posts based on a keyword search can be displayed, which enables you to see and act upon a real time listing of posts coming from each service. »

Rainbow Stream is a smart and nice Twitter Client on Terminal.

YoruFukurou (NightOwl) is a Twitter client for Mac OS X, designed for Twitter addicts. It provides powerful functionality through simple user interface.

"Tweet It!" is designed with every single Windows device in mind. From phone with touch screen to desktop PC with mouse and keyboard you'll have great expirience. And Continuum support for pleasant PC like Twitter browsing when you are away from it.

Oysttyer is a console text-based command-line Twitter client and Perl platform, fork of ttytter