Hoot Suite

Hoot Suite:
HootSuite is a website and online brand management service, which publishes to websites such as Facebook, Twitter, LinkedIn, Foursquare, MySpace, and WordPress. It is also a Twitter client.
The service, created by Invoke Media, but later spun off as a separate entity, was founded in November 2008 and launched in December 2008. Version 2 of the client was released on July 31, 2009.The iPhone version of HootSuite was released on December 9, 2009. An Android OS(operating system) version of the application also exists.

Tweetdeck

Tweetdeck:
TweetDeck is an Adobe AIR desktop application for Twitter, Facebook, LinkedIn, Google Buzz, Foursquare, and MySpace. Like other Twitter applications it interfaces with the Twitter API to allow users to send and receive tweets and view profiles. It is the most popular Twitter application with a 19% market share as of June 2009, following only the official Twitter.com website with 45.70% share for posting new status updates. It is compatible with several operating systems including Microsoft Windows, Mac OS X and Linux. An iPhone version was released on June 19, 2009 and an iPad version was released in May 2010 as well. An Android version was recently made available after a public beta period.

Seesmic Desktop

Seesmic Desktop:
Seesmic is a San Francisco based startup company that develops social networking clients for sites like Twitter and Facebook that run on the web, mobile devices, and the desktop. It was created by French entrepreneur Loïc Le Meuer.

Nomee:
this software gives you the option to "follow" your contacts across more than a hundred social networks including twitter , my space, LinkedIn and Facebook. It even supports wordpress and blogger weblogs. You get notifications, and you can also make posts, comment and reply to coments. Nomee,however, can be overwhelming at times and--given all the servicesinvolved--can be bandwith guzzeler. But once it gets going, you're in social networking heaven.
Get it from: www.nomee.com

Social Networking Apps

Social Networking Apps:
With most of us being registered with at least two to three different social network services, keeping track of all our accounts can prove to be quite a task. Thankfully, there are a few apps out there that are one-stop solutions to keep you in touch with your professional contacts on LinkedIn, share your pictures on Flickr, drop your pearls of wisdom and showers of daftness on Twitter, and even display your wild side on Orkut. Here's a list of six such apps. :)