1. Tweet a file : Tweetafile brings an important email functionality to the simple world of Twitter – attachments. Through Tweetafile, Twitter users can send any files (images, PDFs, Docs, videos… whatever) to all of their followers or via direct message to individuals.
2. Remember The Milk : If you use Remember The Milk to manage your tasks, you can do so via twitter using this app. Add Remember The Milk as your twitter friend and simply DM to add or interact with your tasks.
3. Twittonary : If you are new to twitter, some of the words twitter users use can be quite confusing. Get help from a twitter dictionary and learn the “twitter lingo.”
4. Twonvert : 140 character limitations at times can really hold you back. This app converts your text into SMS shorthand language and allows you to say more with less characters.
5. Twist : Allows you to see “hot trends” on twitter. You can also use the search box to see what people are saying about a particular thing and how much buzz it is creating.
6. WhosTalkin : Although this app isn’t specifically for twitter, it is a very useful twitter tool. It allows you to search conversations that you are interested in. This helps you interact with like minded people or the whatever subjects interest you at that point in time.
7. TweetWhatYouSpend : Manage your spending online using twitter. Create an account and use Twitter’s “DM” feature to send tweets. You can export a spending journal later as an Excel or CSV file.
8. TwitterJobSearch : This service allows you to find job postings on twitter. If you are looking for a “web design” gig, simply enter web design to see what jobs are available related to web design.
9. IsTwitterDown? : If you are a heavy twitter user this service might be quite useful. It allows you to find out if twitter is down for everyone else or just for you. The page displays a simple answer “Yes” or “No.”
10. Twiddeo : Upload videos to Twiddeo from your camera phone while on the go. The service then generates a link and posts it to twitter for your friends and followers to see.
11. TwitterCal : This tool connects your twitter account to your Google calendar. You can add events to Google calendar from twitter by sending direct messages to gcal.
12. TwitterFeed : Twitterfeed helps you send your Blog RSS feed or atom to twitter and also lets you track the number of clicks your feeds are generating.
13. PollDaddy : Create polls and post it directly on twitter. This can be extremely valuable when you are researching a subject or need user feedback.
14. LinkBunch : Due to character constraints, it can be quite hard to send more than one link in a tweet. If you need to send multiple links in one tweet (example : a post that has part1,2,3…), this service can be useful. It collects all links and gives you one shortened link that you can post on twitter.
15. Tweetdeck : One of the best desktop twitter apps out there. Tweetdeck helps you sort your friends and followers in groups and also helps you manage replies, DMs and search results.

1. Remember Why People Follow You- This is the first thing you have to figure out. Unless they’re just desperate for more friends, people usually have a specific reason for following you. If your Twitter account is for professional networking, they most likely want to hear your thoughts on relevant industry topics. In other words, they don’t want to read about you clipping your toenails or getting in a fight with your significant other.

2. Determine Why People Quit You- It’s a sad fact of Twitter life, but people will unfollow you at some point. You need to figure out why they’re doing it. One handy tool for doing this is Qwitter. This will send you an alert letting you know the exact moment someone stops following you. It will show your most recent Tweet with the hopes that will shed some light on the situation. If that doesn’t help, ask yourself if you’re living up to your expectations from tip #1.

3. Interact with Your Followers- Twitter is a social tool. So, you need to be social. Don’t just send one-way Tweets. Interact with the people you’re following. Someone is much less likely to drop you if you engage with them on a regular basis. Remember, social networking is about building connections. The only to build strong connections is to chat it up.

4. Don’t Over Tweet- Maybe I’m being anal, but one of the things that leads me to unfollow someone is when they drop 50 Tweets in the span of a few short minutes. It’s like the guy at the conference who tries to take over the show by asking 10,000 questions. Let everyone share the floor. Tweet your heart out, but just be careful not to overdo it.

5. Don’t Under Tweet Either- If you don’t give your Twitter account any attention, you’re begging to be wiped away when someone starts trimming their following list. It goes back to tip#3—if people don’t know you, they’ll have little problem dropping you like a bad habit. Keep your visibility up by making at least a few quality posts each day.

6. Keep Self-Promotion to a Minimum- Is there anything more disappointing than following a new user only to find that every one of their updates is a link to some crappy blog post they wrote? Even worse is when they constantly Tweet about how great their company is or why you should do business with them. Look, a little self-promotion is expected. But keep it at a minimum. It’s not an infomercial; it’s Twitter.

7. Lend a Helping Hand- Instead of constantly promoting yourself, lend a helping hand to some of your connections on Twitter. If you see somebody wrote a good post, do them the favor of Retweeting it. They’ll be appreciative, and it shows others you aren’t just in it for yourself.

8. Be a Resource- If you really want people to continue following you, make it impossible for them to leave by making high quality updates. Whether this is linking out to a great tool or article or simply giving a thoughtful opinion in a discussion, people won’t stop following someone who’s a great resource.

9. Stop Whining- Here’s a surefire way to start losing followers—constantly complain about your life. One of the best things about working from home is I don’t have to listen to people gripe all day about inconsequential things. No one cares if McDonalds messed up your order or if your boss is a jerk; stop whining!

10. Be Yourself- Yes, this sounds like something out of a cheesy motivational video, but it’s true. People follow you because they care what you think. Just be yourself, and people will respect that. It’s the only way you’ll truly stand out from the masses.

11. Don’t obsessively study guides to using Twitter.  (There are a lot.)  You’ll drive yourself crazy and waste valuable tweeting time

12. Don’t edit out your tweets about the weather.  I talk about the weather a lot.  It’s not deliberate, maybe it’s because I live somewhere wild and wet, but it’s a great ice breaker and way to get to know people in other parts of the world

13. Don’t edit out your tweets about what you’re eating.  You’re sure to find someone who’s interested in or revolted by your food choice, or needs a translation.  (Haggis, neeps and tatties anyone?)

14. Don’t be afraid to ask questions.  You don’t need to know it all on Twitter.  Ask good questions and you’ll get a flood of witty, helpful responses in return

15. Don’t stick to one time of day.  Your Twitter stream will vary according to time zone, who’s awake, what kind of mood they’re in.   You too.  Experiment and see what suits you best

16. Don’t go so fast you miss your @ replies (replies sent to you).  Invest in replying to those who reply to you and you’ll start to make friends, not just pick up followers

17. Don’t follow people you think you ’should’ follow.  It’s pretty dull following a whole lot of social media A listers.  Twitter’s full of interesting, quirky people.  Leave room in your stream for people who aren’t ‘anyone’, just someone.

18. Don’t forget to share pictures.  People enjoy clicking on a link to a picture.  It’s quick, easy and doesn’t require any mental effort to read another blog post.  Plus it’s a great way to share another part of your world.

19. Don’t stick to talking about your core brand.  Share something of yourself.  Talk about things you’re interested in.  You never know where it might lead.  Apparently I’m to lead a Twitter class on beginner’s Gaelic.  What does this have to with this blog, with Confident Writing, with my professional reputation?  Not a lot.  With me? Mucho.

20.  Don’t worry about the numbers.  And don’t tweet about your numbers: it’s really not that interesting to anyone else.  Focus on the conversation.

21. Don’t worry about unfollowing people.  So what if they’re clocking your clicks with Qwitter?  We’re all following and unfollowing all the time.  It’s one of the reasons I like it: the realisation that there’s no such thing as Twitter because everyone is enjoying a different conversation with a different pattern of people

22. Don’t worry about leaving Twitter for weeks at a time.  ‘Twitter’ won’t care because Twitter doesn’t exist.  Most of the 100s of people following you won’t notice either way.  Your friends will – and will be glad to see you back.

23. Don’t forget to be yourself, whatever that means

24. Don’t think about the fact that the world can read your Twitter stream.  (You have remembered it’s open to all to read haven’t you?)  It might just cramp your style

25. Don’t thank your followers for following.  I mean really: how much effort does it take me to click a link on your name? I don’t expect thanks for following.  And I don’t expect you to mind if I click away later.

26. Don’t reread your own Twitter stream: it might scare you

27. Don’t post your Twitter stream to your blog.  Unless you’re stuck in broadcasting mode your stream will make no sense to readers of your blog.  It might just make sense to people following your stream, but it really makes no sense at all out of context.

28. Don’t try and follow all the links you find in your stream.  It’ll make your head explode. (Apparently Twitter serves up a new post every 2 seconds.)

29. Don’t broadcast all the time.  (It’ll sound like you’re not listening.)  Or reply all the time.  (It’ll baffle the people who follow you.)  Or try and find the perfect balance between the two. (You never will.)

30. Don’t follow my rules – or anyone els’es. But you might want to set some of your own.  (Mine are: Don’t talk about clients in an identifiable way.  Ever.  Don’t drink and tweet.  Don’t DM anything I couldn’t cope with others reading if something scary happened to the system.  Don’t be unkind.)

Twitter Clients for the iPhone

Hahlo – Nice looking Twitter client with simple navigational menu system.

iTwtr – Download tweets to iPhone for viewing even when not connected to wifi, 3G or even Edge.

PocketTweets – Slick client for the iPhone

Twitteriffic – One of the most popular clients for Twitter on the iPhone.

TwitterFon – My personal favorite Twitter client for the iPhone because of simple navigation buttons that allow you to jump from one area to another.

Niche Twitter Apps for the iPhone

AirMe - Send photos from your iPhone to Twitter with this free app which includes a Twitter client.

iMapMyRun – Lots of features for runners including Twitter access.

Jott – Record voice messages from your mobile device and post links to it on Twitter.

Locly – Location tracker with Twitter integration that shows tweets in your area.

Loopt – Another location tracker with Twitter connection but also other services like Yelp.

Twinkle – Location based Twitter app that utilizes the GPS feature.

Twitfire – Upload photos to twitter and more.

Twitterlator – Manage multiple twitter accounts.

Twittervision – A world view of tweets from around the globe in real-time.

Twootball – Track all football scores and teams via this Twitter app.

T-Mobile G1

TwidRoid – Probably the most popular full-featured Twitter client for the Android G1 now with GPS support.

Twitli – Simple client for Android devices that translates languages.

TwitterDroid – Not to be confused with TwidRoid, TwitterDroid was created as a clone of the popular Twitterific client. Not as easy to install as all of the other apps because it requires some manual sets.

BlackBerry

Blackbird – Twitter client for the BlackBerry. Here’s the over-the-air installation file.

TinyTwitter – Actually works not just on BlackBerries but also Windows Mobile devices and any Java-enabled mobile device.

TwitterBerry – The most popular Twitter client for CrackBerries. I used this one for a while on different BlackBerry models.

Windows Mobile

ceTwit – Windows Mobile client for Twitter written in c# and .net framework.

GPSTwit – Adds location tracking to Twitter on Windows Mobile devices (iPhone too)

PocketTwit – Free client (donations accepted) that works with Twitter and Identi.ca accounts.

Twitter2Go – Very basic Twitter app with limited features.

TwitToday – Small app for Windows Mobile devices with standard Twitter features.

Twitter Answers – The Twitter version of Yahoo answers. Ask and answer questions with this application.

Quakk – Open source Twitter client, which means not as quick and easy to install and update.

Smartphones

twitxr – Upload photos to Twitter (Native clients available for iPhone, WinMo, Nokia/Motorolla)

Moblf - runs on many platforms and connects to Twitter and Friendfeed

MobyPicture – Connects to Twitter, Flickr and other networks on different mobile platforms.

TreoTwit – Twitter client for the Treo and its Palm OS.

Twibble – Twitter for the Nokia N95 with GPS support.

Non-Smartphones

JibJib – Tiny Twitter client for non-smartphones for basic functions

jTwitter – Java client for Twitter that will work on many different mobile devices including non-smartphones

psyhzzz – Extremely tiny twitter updater that works on most non-smartphones

TinyTwitter – Works on many Java enabled devices as well as Windows Mobile phones.

Twim – Java client that will work on most non-smartphones.