Unless you’ve been hiding under a rock, in a cave or in the mountains, then I’m sure you’ve heard of Twitter. The microblogging tool has become so popular that it’s the standard to have a  Twitter app on your smartphone or tablet; you can rest assured that the Apple App Store has plenty of them to choose from.

The average Twitter user is aware of all the basic features that come with a Twitter client. These are the expected features such as being able to view the timeline, replies/mentions and DMs (direct messages).

It’s also expected that you’ll be able to reply to other tweets, retweet others, and add tweets to favorites. Let’s not forget about searching – some clients may not show trending topics, but you at least should be able to do a simple Twitter search with the app.

This now brings us to this list of the best Twitter clients for the iPad and iPhone. The apps below go above and beyond the “average” Twitter client. They’ll allow you to do much more than what is expected from an average app. Their additional features, superior functionality, and quick speed are what make them stand out.

Therefore, we won’t be looking at the basic features, instead, we’ll focus on the unique features that make each app worth your time and money.

Most Feature Rich Twitter Apps for iPhone and iPad

Tweakon ($1.99)

Tweakon

Tweakon calls itself the “ultimate Twitter client for the iPhone and iPad with categories, auto-tweets, auto-replies, and much more.” There is a free lite version as well as the paid version.

  • separate inbox for unread tweets with visual notifications
  • auto-scroll and scroll on demand
  • shake device to enter full-screen mode
  • upload pictures
  • automatically shortens links via bit.ly
  • view links within the app or open in Safari
  • add users to lists
  • view daily and weekly trending topics
  • auto refresh timeline
  • mark all tweets as read

Get the Tweakon universal app

HootSuite (Free)

HootSuite

HootSuite is known as the “social media dashboard” because it gives you access to numerous social services in addition to Twitter. It has native apps for both the iPhone and iPad.

  • multi-column interface
  • update your Facebook profile and fan pages
  • check-in and send shouts on Foursquare
  • translate tweets to/from 50+ languages
  • schedules messages to send in the future
  • view click-through stats for links created with HootSuite’s URL shortener ow.ly
  • add your location to tweets
  • share and store photos and files
  • bump to follower other users via Bu.mp
  • real-time Twitter search
  • monitor keywords, hashtags, and lists
  • save tweets as drafts and finish them later
  • see conversation history so you know what tweet(s) other users are referring to
  • start you off where you left off before closing the app
  • send links to Instapaper to read later
  • built-in push notifications

Get HootSuite for iPhone or iPad

Trickle ($.99)

Trickle

Trickle is not a full-featured Twitter client, it’s simply an app that turns your tweets into a slideshow. Tweets are automatically pushed in from the right and displayed individually.

  • hands-free usage (displays on its own)
  • lets you add and save Twitter searches
  • retweet and add tweets to your favorites
  • double tap a tweet to open it up your favorite Twitter client

Get the Trickle universal app

TwitBird (Varies)

TwitBird

TwitBird is an all-in-one customizable Twitter client with advanced features. It offers 3 different versions to choose from: free, premium ($1.99), and pro ($2.99).

  • includes 4 themes and lets you add your own custom background
  • send links to Instapaper or Read it Later for later reading
  • attach a video, audio, or the song you’re listening to
  • inline view of images
  • built-in address book
  • add your location to your tweets
  • search for users nearby and view them on a map
  • built-in push notifications for mentions and DMs
  • customizable dashboard
  • save tweets as drafts for later editing

Get the free, premium or pro TwitBird app

Twitterrific (Free, in-app upgrade)

Twitterrific

Twitterrific has native apps for both the iPhone and iPad. The name is a playful mixture of the words Twitter and terrific.

  • save custom searches
  • send links to Instapaper or Read it Later for later reading
  • combine timeline view that can be filtered to display only mentions, DMs or favorites
  • timeline filtering – block tweets containing specific keywords and hashtags
  • built-in themes
  • instant translation of tweets into your device’s native language
  • push notifications via 3rd party apps like Boxcar
  • view conversation threads between users
  • email tweets to friends
  • inline view of images from mlkshk and Pikchur

Get Twitterrific for iPhone or iPad

Echofon ($4.99)

Echofon

Echofon is more than just an iPhone and iPad Twitter client, it also has a Mac app, Firefox Addon and Windows app (coming soon). It has both a free and pro version.

  • sync your tweets between apps
  • share photos and videos
  • add location to your tweets
  • built-in push notifications for mentions, DMs, when one of your tweets is favorite, or when you’re followed by someone new
  • you can mute push notifications during time specified in settings
  • view images and videos inline
  • mute users, Twitter clients, and hashtags within your timeline
  • pick up where you left off – no matter which app you were using
  • unread tweets are marked with a blue arrow
  • find out why a topic is trending via What the Trend

Get the free or pro Echofon app

Twitter (Free)

Twitter

This is an official Twitter app by Twitter.com. While it doesn’t offer a tremendous amount of features, it has great functionality, a sleek design, and is totally free.

  • real-time search
  • view saved searches and trending topics
  • see suggested users to follow
  • share photos and videos
  • view user locations on a map

Get the official Twitter app

TweetList ($2.99)

TweetList

While TweetList is a full-featured Twitter client, it focuses mainly on creating and managing Twitter lists. It has both a free and pro version.

  • view conversations between users
  • customizable interface
  • themes – light and dark
  • push notifications via Boxcar
  • VoiceOver accessibility
  • write longer tweets via TwitLonger
  • send links to Instapaper or Read it Later for later reading
  • mobilizer support for optimized web page viewing on your device
  • autocomplete when entering username and hashtags

Get the free or pro TweetList app

Tweetlogix ($1.99)

Tweetlogix

Tweetlogix has a lot of great features to help to enrich the Twitter timeline and give you a great experience. The app is not yet optimized for the iPad, though it can be used on it.

  • inline images
  • share images, videos and the current song you’re listening to
  • mute specific users and hashtags
  • search for Twitter users nearby and view them on a map or list
  • built-in themes – light and dark
  • auto-refreshing of the timeline
  • send links to Instapaper or Read it Later for later reading
  • tweet more than 140 characters via TwitLonger and twtmore
  • keeps track of your recently used hashtags
  • add your location to your tweets
  • translate and email tweets
  • save drafts for later usage
  • see why something is trending via What the Trend
  • customize your tabs
  • view conversation threads
  • retweet the old or new way
  • use bit.ly URL shortener or your own custom shortener

Get the Tweetlogix app

Tweetbot ($1.99)

Tweetbot

Tweetbot is a beautifully designed Twitter client with a dynamic interface, sounds, and animation as well as customizable smart gestures. The app is not yet optimized for the iPad, though it can be used on it.

  • sounds and animation
  • multiple timelines – you can set a list as a timeline
  • customizable smart gestures and navigation
  • send links to Instapaper or Read it Later for later reading
  • shorten links using Cloudapp
  • receive push notifications via Boxcar
  • save drafts for later use
  • add your location to your tweets
  • translate tweets
  • send tweets and messages in the background
  • view conversation threads

Get the Tweetbot app

SimplyTweet 3 ($4.99)

SimplyTweet

SimplyTweet is loaded with features that make using Twitter fun and easy. There is currently a free and paid version for the iPhone and iPod Touch. The app is not yet optimized for the iPad, though it can be used on it.

  • push notifications for mentions and DMs with customizable sounds
  • shows the number of new messages on the app badge
  • send images, tweets, and DMs in the background
  • send DMs from the actual iOS Contacts apps – tap on the Twitter DM field in contacts to start a new DM
  • 5 built-in themes – silver, twilight, yellow, bubbles, pink
  • photo search – search for images shared on Twitter
  • save drafts for later use
  • shrink tweets longer than 140 characters so that they’ll fit with Tweetshrink
  • Send DMs longer than 140 characters
  • use TextExpander to type faster by using short abbreviations that expand into long snippets
  • send links to Instapaper or Read it Later for later reading
  • See why something is trending via What the Trend
  • upload images and videos and share on Posterous, TwitPic, yFrog, TwitrPix, or Twitvid
  • view conversation threads
  • make your text bigger if needed
  • hide avatars of those users who are on your blocked list

Get the free or paid SimplyTweet app

Star Tweeter ($1.99)

Star Tweeter

Star Tweet is simple, yet unique in that it lets you rate users with stars – on a scale of 1-5. You can then view friends in your timeline based on those ratings. The app is not yet optimized for the iPad, though it can be used on it.

  • give users ratings, nicknames, and tags which can then be used to filter your timeline
  • auto refresh your timeline, mentions, and DMs
  • real-time search and it saves a history of your searches
  • manage and save search terms
  • view trending topics in real-time, for the day, or for the week
  • view nearby tweets on a map
  • view conversation threads
  • upload images

Get the Star Tweeter app

Seesmic (Free)

Seesmic

Seesmic lets you view and update multiple social networks at once besides Twitter. Unfortunately, it is currently not optimized for the iPad, but due to its setup and efficient use of “Spaces,” hopefully it will be soon.

  • supports Twitter, Facebook and Ping.fm – which let’s update 30+ social services at once
  • post to one or more accounts at the same time including Facebook Pages
  • customizable “Spaces” which can display whatever you like such as multiple accounts, searches, trending topics, lists and more
  • share updates with friends via email or store them in Evernote
  • add your location to your tweets
  • save searches
  • upload and share photos to the services of your choice

Get the Seesmic app

Twittelator ($4.99)

Twittelator

Twittelator is one of the most advanced Twitter clients you’ll find with all of the features to match. There is currently a free and pro version. The app is not yet optimized for the iPad, though it can be used on it.

  • update your status on Facebook
  • create and tweet audio, the current song you’re listening to, and high-resolution images
  • record, edit and tweet videos (camera required)
  • save drafts for later editing
  • read tweets when offline
  • add a map with your location to your tweets
  • find nearby tweets and view them on a map
  • create and share your own theme or use one of the 4500 shared themes
  • has a built-in browser for viewing links, videos, and audio
  • translate tweets
  • auto refresh the timeline
  • customize the categories that show on the Tab Bar
  • find your friends using the contact search feature
  • turn on/off the capitalization and autocorrect features
  • 3 different retweet formats
  • shrink tweets before sending so that it will fit within the limits via TweetShrink
  • split up your tweets and DMs that are over 140 characters or use TwitLonger to include it all in a single tweet
  • see recently used hashtags
  • includes 540 emoji and dingbat symbols and icons
  • Song.ly MP3 links include a speaker button so that you can listen within the app
  • get an explanation of any tag that’s used in a tweet via TagDef
  • search for Twitter lists and view super lists of top tweets in any topic
  • use TextExpander to type faster by using short abbreviations that expand into long snippets
  • use FollowCost to see how “expensive” it is to follow a specific user
  • use TweetBlocker to see if a specific user is a Twitter spammer
  • use Favstar to see popular tweets from any user
  • see why something is trending via What the Trend
  • send links to Instapaper or Read it Later for later reading
  • add tweets to to-do items via OmniFocus
  • add any user to your bookmarks for easy referencing

Get the free or pro Twittelator app

Scopy ($.99)

Scopy

Scopy is “the Twitter client for photo lovers.” It “extracts photos from your timeline and presents them quickly and beautifully.” Unfortunately, Scopy is not yet optimized for the iPad, but with an interface this gorgeous, let’s hope it’s coming soon.

  • browse images from your friends or search for images by topic or keyword
  • take snapshots and apply 1 of 8 effects to it from within the app
  • type of effects include: xprocess, noir, golden, chill, vintage, delta, sakura
  • browse all photos from your timeline via list or thumbnail mode
  • add your location to your tweets and view the location of others on a map
  • find your friends and others to follow
  • supported services for viewing images include: Flickr, Imgur, Instagram, Plixi, TwitPic, yFrog, Posterous, Skitch, and more

Get the Scopy app

What is your favorite Twitter app for the iPhone and/or iPad touch? Why is it your favorite? Feel free to share your thoughts and opinions in the comments below.