Below are some helpful Twitter-based tools
tweriod.com: Tweriod analyses your tweets and followers to let you know the best time to tweet. Tweeting then will get you more responses/retweets.
tweetwally.com: Here, you can see a page that collates tweets with a particular hashtag or keyword — makes it easy to track a topic on twitter.
twylah.com: Twylah aggregates your tweets and shows links/images tweeted by you on a single web page. Your followers can easily get a glimpse of topics that you tweet about. The service is currently in beta so you have to request an access code.
manageflitter.com: This tool categorises your followers — inactive, no profile pic, spam or by language. Use this information to unfollow the irrlevant ones. You can also schedule tweets.
tweetalarm.com: Get notified (by email) when someone mentions specific keywords on twitter — notifications can be instant, daily or weekly.
monitter.com: Here, you can search for a particular topic or keyword on twitter and sort the results based on the location of the tweeter.
nurph.com: At Nurph, you can create a virtual chat room where followers can tweet-chat with you. You also get a robot assistant that learns from the ongoing conversation and can reply on your behalf.
useqwitter.com: Sign in to Qwitter to find out who unfollowed you. The free version lets you track a single twitter account — it updates weekly.
futuretweets.com: Ever wanted to send automated tweets in the future? Here, you can schedule a tweet for later (day or time). Hint: use it as an alibi.
twit-twoo.net: Create an account & they’ll tweet you with reminders for an event or happening. Use it to remind you of anniversaries or to-dos.
splitweet.com: Effortlessly manage multiple twitter accounts with this handy tool. Great for corporate use too.
flashtweet.com: Simply put, FlashTweet allows you to acquire targeted followers. You can also use it to mass follow based on a keyword or location.
twitchamp.com: Like a friendly competition? Compare how you’re doing on twitter with your friends. You only need to enter the usernames.
tweetcube.com: Use this free service to share files (up to 10MB) on twitter. You can share any sort of file, but the catch is that it gets deleted in 30 days.
tweetstats.com: Just enter your username here to get detailed stats — tweet density, replies, retweets — it’s all there.
tweetwrappr.com: Useless but funny, TweetWrappr lets you ‘gift wrap’ a tweet and send it to someone as a URL.
visibletweets.com: Just enter a keyword or hashtag and watch as everything gets animated for you in real time.
tweetrans.com: Want to be a global tweeter? Use this tool to send tweets in multiple languages in one step.
tweepsmap.com: Simply shows you where in the world your followers are.