Talon for Twitter - Elegantly designed, ad-free Twitter experience for Android
Tweedle App - Notion is nice but sometimes all you need is an app like Tweedle.
YoruFukurou - YoruFukurou (NightOwl) is a Twitter client for Mac OS X, designed for Twitter addicts.
Plume - App for writing documents, scripts, books and more.
Plume for Twitter - Plume for Twitter is a highly customizable and eye-catching app that will change the way everyone interacts with Twitter.
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.