The key view in Carbon is of course the timeline screen, which gives an overview of recent tweets from people you are following. There's optional support for inline images (those mentioned in tweets) and icons show the type of information included in a tweet (videos, reply, location and so on). Tapping on a tweet open up the tweet screen where the full details of the tweet are displayed (including high resolution inline media) and the profile of the tweet is a single pivot away.
The mention screen shows you the latest tweets directed at you and, where relevant, includes a conversation view, so that you can follow the story line of a series of tweets.
Carbon implements a number of gestures that help speed up the use of the timeline and related screens. For example, a double tap on a tweet lets you jump straight to the reply screen. A long press on a tweet pops up a context sensitive quick actions list (e.g. reply, retweet, quote).
A main menu gives quick access to your own profile information, but also lets you quickly swap between different Twitter accounts.
One of aims of the Carbon app is to provide a high level of integration into Windows Phone standard UI. Thus there are Live Tiles for each account, for composing tweets (with the option to choose which account to tweet from), and for search results (e.g. #hastag). There's also support for Toast notifications and background updates.
In the same way some of the less commonly supported Twitter functions have been implemented in Carbon. For example, the QuickLine page, described by the developers as a swiss-army timeline view, gives quick access to lists, retweets and saved searches. Full access to profile information (past tweets, friends, followers, favourites and lists) is also provided.
Other features include support for threaded direct messages, image upload (native Twitter, TwitPic and YFrog), support for multiple short URL services (Twitter, Bit.ly, Bit.ly Pro and Goog.gl), support for Read It Later and Instapaper, tweet translation, and more.
Carbon is best suited to power users, who want to maximise their Twitter usage on the go. At first the application can be a little overwhelming, but once you start using it, you'll notice and appreciate small touches and functionality that combine to create one of the most compelling Twitter implementations for Windows Phone.
The developers are not standing still; in the future they plan to add support for push notifications, support more services (e.g. image upload and inline images) and further refine the UI. The next version, 1.2, is due to be released on February 15th, is set to include performance improvements, inline images in the timeline and additional gesture support.
More information is available on the Carbon WP7 blog, incluing the story behind some of the app's problems in passing the submission guidelines.
Carbon, which has been published by Yalla Apps on behalf of dot1ne, can be downloaded from the Window Phone Marketplace. It costs £.149 / €1.99 $1.99, a trial version will be available after the next application update..