Twitter is no longer a little known platform for bloggers to communicate on. These days, even large corporations are realizing something many smaller businesses have known for a while . . . Twitter is a powerful PR tool.

Making the site even more useful for public relations and networking are the myriad of third party applications that seem to be multiplying at an exponential rate. Rarely does anyone just use the Twitter.com website . . . now you can tweet from your iPhone, your desktop or even within your browser. These applications are quite valuable for anyone looking to promote their business and if you are in the market for something that will make business and publicity just a bit easier, then this list is for you!

Advertising for Cash

1. AdCause

adCause matches advertisers with publishers (twitter users). Publishers will get paid show ads in their twitter feed. The more influence you have on twitter, the more money you will make.

2. FeaturedUsers

When you purchase impressions, your Twitter profile is displayed on the Twitter apps in the FeaturedUsers.com network. The more impressions you purchase, the more often your profile is displayed.

3. Izea

A sponsored conversation is a social media marketing technique in which brands provide financial or material compensation to bloggers in exchange for posting social media content about a product, service or website on their blog. IZEA created the sponsored conversation space in 2006 and has initiated nearly 1,000,000 sponsored conversations to date.

4. Magpie

An advertiser creates their ad message and selects some keywords that will help identify the best Magpie-Twitterer for the campaign. Magpie identifies the most influential Magpie-Twitterers for a campaign based on the selected keywords and pays them for auto-tweeting the campaigns.

5. Twittad

Twittad is a Social Media Affinity Network that connects Advertisers and Twitter users. By using Twittad, Twitter users can monetize their profiles & Advertisers can reach ALL of Twitter; the Website, 3rd Party Applications and Mobile Devices!

6. WhatsYourTweetWorth

Enter your Twitter ID to get a feel for how valuable you are on Twitter.

Business

7. Chipin

Embed the ChipIn Widget on your favorite Web site or create your own ChipIn page at yourname.chipin.com.Let your social network contribute via ChipIn’s secure service and collect your funds via PayPal.

8. CoTweet
CoTweet is how business does Twitter. CoTweet allows multiple people to communicate through corporate Twitter accounts and stay in sync while doing so. No dropped balls, no stepping on each other’s toes.

9. ConnectTweet

Groups and businesses are made up of many people, not faceless Twitter bots or a single person’s voice. ConnectTweet facilitates your voices combining.

10. JointContact

Joint Contact is a state-of-the art project collaboration tool for sharing and managing information that is used by business owners, project managers, freelancers and independent professionals.

11. Monitter

It’s a twitter monitor, it lets you “monitter” the twitter world for a set of keywords and watch what people are saying.

12. MyTweetSpace

Make your Twitter page stand out with a unique background. MyTweetSpace offers a variety of options to brand your profile page. Make your business memorable with the right background.

13. Postica

Create and post sticky notes anywhere you like. Then share with Twitter friends.

14. SplitTweet

Easy management for multiple Twitter accounts and brand monitor. The definitive twitter client for heavy & corporate users.

15. Tipjoy

Simple social payments for great people, causes & content. Raise money via Twitter.

16. TrackThis

No more refreshing pages. No more wondering if packages have arrived yet. With TrackThis, we’ll send you near instant updates via Email, SMS messaging, RSS feeds, Facebook, or Twitter. We track UPS, Fedex, USPS, DHL and several other carriers.

17. TwitTrans

Translate your tweets to any language by human translators.

18. Twittertise

Twittertise allows you to advertise on Twitter and track the success of branded communications with your customers. Using Twittertise you can schedule your communications on Twitter and using URL tracking technology measure the effectiveness of your traffic driving techniques on the platform.

19. TwitterHawk

Real time marketing engine that allows you to start talking with people discussing your topic.

20. Twilert

Twilert is a Twitter application that lets you receive regular email updates of tweets containing your brand, product, service, well any keyword you like really.

21. twtQpon

TwtQpon is an online coupon creator that helps you to create and distribute coupons on Twitter, Facebook and other social media sites.

22. Twitterlights

If you find something you want to send to your Twitter followers send it through i-Lighter.  On any web page you are reading, Right Click and click Twitter This! Type in your 140 character twitter message. The URL of the web page will automatically be sent as a TinyURL.

23. Twitzu

A service that lets you manage events, announce them, and handle RSVPs.

24. Twtmarket

It is a cool, simple to use twitter application that connects supply and demand in the twittersphere.

25. Vacatweet

Don’t let your business be silent on Twitter. Set up vacation tweets that will automatically go out when someone tweets you directly.

26. Xpenser

We were fed up with how painful expense reports and tracking were. After many experiments we found a workable solution: record expenses as soon as they happen and forget about them. Xpenser lets you do just that – record expenses via whatever means are available to you quickly and painlessly.

Blogging

27. Add to Any

Wordpress plugin to help readers share, save, bookmark, and email your posts and pages using any service, such as Facebook, Twitter, Digg, Delicious, and over 100 more social bookmarking and sharing sites.

28. MyTwitter

MyTwitter allows users to display their recent Twitter status updates (tweets) on their Wordpress site and update their status through the Options page.

29. Ping.fm

Ping.fm is a simple and FREE service that makes updating your social networks a snap!

30. SiteVolume

Similar to Alexa, this site will allow to see how many time a particular term has been used on Twitter, Digg, MySpace, YouTube, and Flickr. It’s also possible to check multiple terms and see visuals of the results.

31. Twitterfeed

Twitterfeed allows you to post your RSS feed from your blog on Twitter.

32. Twitpress

Submits a user definable tweet to your twitter account notifying any twitter followers or friends that a new blog entry has been published on your blog.

33. TwitterRibbon

Generates a Twitter Follow Me corner ad ribbon for your site.

34. UpdateThat

A widget that enables your visitors to update their Facebook, Twitter and MySpace status while on your site. You can include a link back to your site.

Email

35. TwInbox

TwInbox seamlessly integrates Twitter into Outlook. It is a perfect Twitter client for any Outlook user, from a Twitter newbie to a business professional.

36. TwitterMail

A user submits his or her Twitter account details at twittermail.com and gets a unique new email address. From that moment on each message this user emails to this unique and secret email address is posted to their own Twitter account.

37. Twimailer

Tired of shallow e-mails from Twitter when someone follows you? Want to know more about the people who are following you? Twimailer is a free service that delivers that information right to your inbox!

iPhone and Other Mobile Apps

38. iTwtr

An open source Twitter client for iPhones.

39. Qik

Qik enables you to share your moments live with your friends, family and the world—right from your mobile phone!

40. Twittelator

Twittelator Pro is the most powerful twitter client for your iPhone/Touch that you can download from the App Store and begin following people and posting Tweets, maps & photos.

41. TwitterBerry

TwitterBerry is mobile client for posting updates to Twitter. It works over the data network, so you don’t need to use SMS.

42. Tweetie

iPhone Twitter client that allows you to handle multiple Twitter accounts, check your timeline, browse friends and tweets and reply to tweets.

Images/Video/Audio

43. Twiddeo

Twiddeo is a powerful but simple service that let’s you do one thing very well: Twitter updates with Video. Upload from the web, your cameraphone and record from your webcam.

44. Twitsay

Call your regional twitsay number (should be a local call) and leave a voice message. Then, go to your Twitter page and listen to your voice message. All your followers can listen to it, too!

Filesharing

45. Acamin

Share files with your Facebook, Twitter and LinkedIn friends. Various options such as email or embedded links available.

46. FileSocial

FileSocial is the easiest way to share files on Twitter. You can upload any kind of file, from pictures to videos,PDFs or Power point… Whatever you want!

47. TwitDoc

Upload your file, shorten the URL, and post a tweet all in one easy step. No sign up needed. Use your existing Twitter account in the form below or download our FREE Adobe AIR desktop client which enables you to drag and drop your files into your tweets.

48. TwitFS

File sharing app for Twitter that offers a free Basic account or a paid Premium account.

Productivity

49. FutureTweets

FutureTweets.com is a free service that lets you schedule your Twitter messages. Send it at a specific time in the future or send a reoccuring Tweet daily, weekly, monthly or yearly!

50. HootSuite

HootSuite is the ultimate Twitter toolbox. With HootSuite, you can manage multiple Twitter profiles, pre-schedule tweets, and measure your success. HootSuite lets you manage your entire Twitter experience from one easy-to-use interface.

51. Jott

With Jott Assistant and Jott for Salesforce, you just call a simple phone number, speak your notes, messages, or updates and hang up.  Then, Jott takes the spoken messages, turns them into text, and sends them to the right destination via email, text message, or web update.

52. JustSignal

justSignal Personal Edition helps you find all of the Social Media content you are interested in, without all the noise.

53. LinkBunch

LinkBunch lets you put multiple links into one small link which you can share over IM, Twitter, email or even a mobile phone SMS.

54. Remember the Milk

You can interact with Remember The Milk via direct messages on Twitter. To add a task to your account, just send your rtm friend a direct message with the name of the task. You can also send one of the commands listed below to do more with your tasks.

55. MyCleenr

MyCleenr is a unique way to sort your friends by their last tweets. It allows you to get rid off all the inactive and useless accounts that you are following!

56. Nozbe

Nozbe – web-based project and time management application to help you get things done!

57. PowerTwitter

Power Twitter adds features to the Twitter Web interface including search and recent searches, Facebook status updates, url translation to page titles, custom settings, inline YouTube, Flickr, TwitPic, Google Maps, song.ly, and more.

58. Strawpoll

Create your own polls that can be tweeted, or take part in other people’s polls.

59. Tempo

Track budgeted hours, projects, and people. Generate invoices to Blinksale and Quickbooks.  Report on projects, people, dates and tags with detailed charts to visualize time and uncover trends.

60. Timer

Timer allows you to receive timed alerts about tasks you should be doing, via Twitter.

61. Toodledo

An easy to use, online to-do list. Get organized, stay motivated, and be more productive.

62. TweetLater

TweetLater allows you to set tweets to be posted at a specified time, so you can be online even when you are nowhere near a computer.

63. TwitResponse

Setup unlimited messages to be delivered to your twitter page when you want. Need a message sent 2 hours from now, no problem, setup a TwitResponse.

64. TweetCube

TweetCube is a 100% free file sharing service for Twitter. You can upload as many images, archives, videos and songs as you want and share them on Twitter with your followers.

65. TwitterCal

A free service that connects your Twitter account to your Google Calendar. Add events in a snap from your favorite Twitter client.

66. Tweetburner

Tracking the links you share on Twitter and Friendfeed.

67. TwitKu

TwitKu is a simple web app that lets you monitor the social networking sites, like Twitter and Jaiku, on a single page. Most of the functionality of the respective sites are reproduced, but there are enhancements not offered on those sites like Flickr thumbnails based on links, auto-expand of “tinyurls,” and more.

68. TweetBeeps

Keep track of conversations that mention you, your products, your company, anything, with hourly updates! You can even keep track of who’s tweeting your website or blog, even if they use a shortened URL (like bit.ly or tinyurl.com).

69. TwitThis

Lets you add any URL to your Tweet stream. It also keeps track of the most popular links in the past 24 hours.

70. Twalala

Using twalala, you can filter tweets out of your stream by keywords and phrases or mute individuals who get a bit too chatty. Finally, Twitter with a mute button.

71. Twitturl

Twitturl is a Firefox extension that allows you to post the current URL of your Firefox browser to Twitter with one click.

72. TweetSpinner

Tweet spinner is an advanced Twitter application to help Twitterers increase their productivity. It allows you to rotate banners, repost dynamic tweets and much more.

73. Tweetwasters

Keep track of just how much time you are spending on Twitter.

74. Twuffer

Twuffer allows the Twitter user to compose a list of future tweets, and schedule their release.

Networking/Social

75. FriendorFollow

Find out who is following you that you aren’t following and vice versa.

76. GroupTweet
Members can broadcast a message to the whole group by sending a direct message to the group’s Twitter account. For example: ‘D initechwebdevs Just committed the latest code to the repository’.

77. Headup

Headup is a Firefox add-on that helps you find cool content related to the stuff you’re interested in. It also lets you instantly find out more information on anyone who uses Twitter.

78. NearbyTweets

Nearby Tweets project was developed by Brian Cray to extend Twitter’s capabilities into its true potential: a geography–centric social tool for networking and a business tool for building customer relationships and monitoring real–time buzz. With Nearby Tweets’ sophisticated geographic layer on top of Twitter people and businesses will find Twitter more relevant, manageable, and fun!

79. Spaz
Spaz is an award-winning open-source Twitter client for the Adobe Integrated Runtime, written entirely in HTML, Javascript and CSS.

80. Spy

spy can listen in on the social media conversations you’re interested in. What do you want to listen for?

81. SocialWhoIs

This website is a proof of concept that a better Social Media can exist ; a social media based on interests and “personal relevancy” instead of popularity.

82. SocialWho

SocialToo is your companion to the social Web. SocialToo can help you become a social power user, by complementing your social experience, giving you all the tools you need to harness the potential of your network. Includes Auto Follow, Follower Synchronization, Auto Unfollow, Block Automatic DMs From Other Services, and Social Surveys and more.

83. Twtvite
Twtvite is an event manager tool that helps you organize Tweetups and make meaningful connections through social media.

84. TweetDeck
TweetDeck is your personal browser for staying in touch with what’s happening now, connecting you with your contacts across Twitter, Facebook and more. TweetDeck shows you everything you want to see at once, so you can stay organised and up to date.

85. TweeterTags

Get the most out of Twitter by finding the right people to share the conversation: Tweeter Tags makes it easy to declare your interests and find new, like-minded friends.

86. TweetEffect

Find out which of your Twitter updates made people follow or leave you.

87. TwitterFriends

To see your relevant network and some stats about your tweeting behavior compared to other Twitter users, just enter your (or another) Twitter username.

88. TwitterLocal

The TwitterLocal AIR Client allows you to watch as many location-based Twitter feeds as you want.

89. twInfluence

twInfluence is a simple tool for measuring the combined influence of twitterers and their followers, with a few social network statistics thrown in as bonus.

90. Twubs
Twubs are Twitter groups built around content aggregated from #hashtags.

91. TweetScan

In the innovative world of Microblogging, one site aims to organize it all. Tweet Scan searches Twitter, identi.ca and other Laconica-based sites with more being added all the time. You can search public messages and user profiles with results available via email, RSS, and JSON.

92. TweetWorks

Tweetworks is designed to make micro-blogging more useful for people and businesses. Tweetworks is based on the simple premise that people like to talk about stuff with other people.

93. TwitScoop

Receive, send tweets, and find new friends instantly, without ever reloading your page. Search and follow what’s buzzing on twitter in real-time.

94. TwitterSnooze

Set a snooze on certain users if they are getting annoying. It’s a temporary way to eliminate the noise from verbose tweeps.

95. Twitterless

Twitterless tells you who stops following you and graphs your follower history over time, making this info available in a variety of useful views.

96. Twollo

Find and Follow Twitterers with similar interests to you – automatically.

News

97. Breaking Tweets
Founded in January 2009, the site has two main goals: 1. to help people enhance their worldview or perspective of global events; 2. to increase dialogue about international news and make the world smaller through conversation and interaction, both on this site and on Twitter.

98. SemNews

Search and browse today’s news sources updated continuously.

99. TweetNews

Another news service that pulls in news feeds through Twitter.

Search

100. TweepSearch

TweepSearch was created to allow people on Twitter to search their followers bio and location information. Twitter doesn’t currently have a bio search and as your Twitter network grows, it’s nice to be able to look through your tweeps.

101. TweetScan

Get email when your keywords are mentioned on Twitter. In the innovative world of Microblogging, one site aims to organize it all. Tweet Scan searches Twitter, identi.ca and other Laconica-based sites with more being added all the time.

102. Twellow

Twellow.com has been designed from the ground up to help you “cut through the clutter”. From our home at Twellow headquarters, we’re actively searching and categorizing millions of inter-personal exchanges available on the internet every day. Twellow.com is thereby able to assist you in finding real people who really matter.

103. Twitterment

Another search engine for Twitter.

104. TwitDir

An improved Twitter directory of users. You can quickly and easily search for anyone to follow, or see the top 100 updaters, followers, etc.

105. Twitority

Search keywords by authority with this handy search engine tool.

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