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.
Twicca - Twicca is a Twitter client for Android that is simply awesome. Features: * Notification
Twitterrific - Twitterific is an app that offers several functions and fun features for your Twitter account.
Tweedle App - Notion is nice but sometimes all you need is an app like Tweedle.
TweetDeck - TweetDeck is your personal browser for staying in touch with what’s happening now.
HootSuite - Enhance your social media management with Hootsuite, the leading social media dashboard. Manage multiple networks and profiles and measure your campaign results.