The web service HootSuite gives you a single online dashboard through which you can manage not just Twitter but also a spate of other common social networks. The basic free version is ad-supported, with a bunch of minor limitations on the services (e.g., you can only add up to five social networks). But, for most people looking to add a modicum of control over multiple accounts, the basic version will do. To set up HootSuite with Twitter, you must give it permission to connect to your account as a native Twitter application, something TweetDeck does as well. The layout is also vaguely similar to TweetDeck: a multi-column screen, with each feed in its own column. A tab selector near the top lets you switch between your own accounts or a page of featured tweets. However, there's no auto-shortening of URLs when typing; you must paste URLs into a subpanel and click to shrink them.
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