Tweetbot - Sync your timeline across your iPhone, iPad, and Mac. Mute tweets by user, hashtag, tweet source, or keywords (including regex). 3rd Party support for image, video, read later, and timeline sync services.
Refined Twitter - A browser extension that improves the Twitter experience
Twitterrific - Twitterific is an app that offers several functions and fun features for your Twitter account.
Tweet Tray - Tweet quickly from your desktop without any distractions.
Fenix for Twitter - A fresh Twitter experience, for Android
Tweeten 2 - A powerful Twitter client based on TweetDeck.