With over 50,000 applications in the iTunes App Store now, it can be a bit daunting to even ponder which applications a new user should start with, or even which application is best for the experienced user.
We've gathered up 40 of what we feel are the best applications in various categories to give you some guidence in what you should be taking up valuable space with on your iPhone and iPod Touch. Communicate with friends, summon a taxi, use your device as a flashlight, kill mutated Nazis in a game, it's all here!

As this is a list of mixed paid and free apps, we do recommend that you check the pricing before adding any of them to your device. Also, all links take you directly to the app in the store, so any of these will launch iTunes on your computer or mobile device.

iPhone Communication Apps

AIM: This ad-supported version of the AOL Instant Messenger allows you to stay logged in all the time if you like, and thanks to the iPhone OS 3 push features, you can always be notified of new incoming instant messages from your contacts. AIM will also allow you to send messages to SMS numbers, connect with users on ICQ, iPhone users can take pictures with the camera to use as buddy icons and a whole lot more.

Fring: Fring can help you cut down on the number of individual applications you need to stay connected with the various instant messaging services. You can use AIM, Google Talk, ICQ, MSN Messenger, SIP, Skype, Twitter and Yahoo!

Skype: This was probably one of the most eagerly anticipated applications for the iPhone, and in record time after its release it had hit over 1 million downloads. While you can't make calls over a wireless connection, you can make them over Wi-Fi which will allow you to make free Skype-to-Skype calls, call regular phone numbers and all of the other Skype features you've come to love.

Yahoo! Messenger: Yahoo! Messenger gives you a nice threaded conversation history view so you can see who said what and when. You can also share images with other users, pass around emoticons, switch your status to invisible and everything else you have come to expect from Yahoo!.

iPhone Game Apps

iShoot: An extremely popular entry in to the artillery game genra. Play against the AI or friends via Wi-Fi to be the last tank standing after all of the dust settles.

Myst: Myst was THE must-have computer game for a long time, and now it has not only made its way to the iPhone and iPod Touch, but they updated the graphics for even smoother gameplay in this atmospheric thriller.

Pac-Man LITE: While this app only allows you to play through the first level of the classic Pac-Man arcade game, do you really need more than that? I'll spoil it for you, in later levels, Pac-Man is chased by ghosts while he eats little dots. You know, kind of like the first level.

Star Defense: The application store is over flowing with turret defense type games, but Star Defense is an easy stand out in this genre for its graphics as wel as its gameplay.

Tap Tap Revenge: Just about everyone has some iteration of this game on their iPhone or iPod Touch. Some are paid, some are free and others are even specific to certain bands, but all of them have one thing in common: fun.

Tetris: The official version of the Tetris game, which has been added to just about every imaginable device known to man since the game first appeared in 1984.

Wolfenstein 3D Classic: Wolfenstein 3D launched the entire first person shooter genre of games, and now the full original game is in the palm of your hand any time you want it.

iPhone Internet Apps

Free Wi-Fi Finder: Have a hankering to get in some time with a free Wi-Fi hotspot? Free Wi-Fi Finder will help you locate hotspots with free access for either the area you are in using the iPhone's GPS, or for an area you designate.

SpeedTest.net Speed Test: The popular Internet speed checker comes to the iPhone and iPod Touch. Think your Wi-Fi connection is acting sluggish? Unsure of your 3G speed? Open up this app and see just how fast your connection really is running.

iPhone Miscellaneous Apps

BubbleWrap: Who doesn't enjoy popping the bubbles on packing material? Well, now you can do it any time you like, and if you feel like making a game of it you can even see how many you can do in the time allotted.

iBeer: "Brew" and "drink" beer with your iPhone or iPod Touch. Select the type of beer you want, then brew it so you can "drink" it any time you want, but remember to shake it up first so it gets “foamyâ€!

Lightsaber Unleashed: Not exactly a game, but just a whole lot of fun. â€Ignite†the lightsaber of your choice, then swing it around to hear those infamous sounds they would make in the movies as they swung through the air.

Virtual Zippo Lighter: Customize your Zippo lighter as you see fit and then “light†it so you can hold up at concerts or just for the fun of playing with it.

iPhone Music Apps

Last.fm: Part social network and part streaming music, Last.fm brings all of your favorite aspects of the popular webiste to your iPhone and iPod Touch. You can share music with friends, mark songs as favorites, check out bios & concert information and a whole lot more.

Ocarina: iPhone users can blow air over their microphone, and then by covering the “air holes†on your screen and moving the phone around to change the pitch, you can create music. Just want to hear what others have done? Just press on the globe icon to hear music that other Ocarina players have come up with.

Pandora Radio: The popular free streaming online radio comes to the iPhone and iPod Touch with an app that brings the most popular features such as thumbs up & down for songs, creating channels and so on.

Public Radio Tuner: Get quick access to the live Internet streams of over 300 National Public Radio stations across the United States.

iPhone News Apps

AP Mobile: The Associated Press has been a name in syndicated news since 1846, and with this iPhone and iPod Touch application, they are continuing to deliver the news well into the 21st century.

BBCReader: Get news from all around the world via one of the most trusted names in news gathering, the BBC. The application will also sync your news so that you can read it while you're offline, like on a cross country flight.

NYTimes: The New York Times brings their biggest headlines from each section of the paper directly to your iPhone or iPod Touch.

iPhone Social Networking Apps

Facebook: While the Facebook application doesn't give you 100% of the normal experience you get from going to the website, but it gets darn close to it. This app allows you to change your status, check what your friends are up to, see new photos they've posted, start chats and more.

LinkedIn: LinkedIn gives you full access to your professional social networking profile so you can stay in contact with those that you've worked with, that have recommended you, when you need to remind yourself of a bit of information before attending a meeting with them amongst many other uses.

MySpace Mobile: While numerous people say they have given up on MySpace due to the annoyances like auto-loading music and glittery graphics. Well, the iPhone app makes it almost fun to check in on the site again as the profiles are stripped down, the site is a breeze to navigate with just a few swipes of your finger and more.

iPhone Travel Apps

Google Earth: Look up any location on Earth with this handy mobile version of the Google Earth desktop application. See satellite photography and information at any time.

Taxi Magic: With just the tap of a few buttons, you can summon a cab in 25 major cities across the United States, while in 4,000 other locations you can do a tap to call disptach. The app also allows you to see where your cab is, and you can also pay your safely and securely with a credit from within the application.

Urbanspoon: Unsure of where you want to eat tonight? Urbanspoon allows you to select things like style, location and cost, and get suggestions of where you might go. Feeling totally random? Just shake the application and see what you end up with!

Yelp: Out wandering around the streets and wonderinf if the coffee house you just past is any good? Look it up on Yelp to see what the user reviews have to say about it.

iPhone Twitters Apps

TweetDeck: The most popular Twitter desktop client comes to your iPhone and iPod Touch and brings its most popular feature with it that you can sort your followers in to different columns so that you can easily see who it is that's talking.

Twittelator Pro: Twittelator Pro packs an amazing array of features in to this Twitter client. You can located nearby users, manage multiple accounts, use autorefresh, a built-in browser for vieing links and a heck of a lot more for a total of 150 features every user will love.

Twitterrific: Twitterrific was one of the first Twitter clients to come out for the iPhone and iPod Touch and remains a favorite even as the market grows more and more crowded. You can manage multiple accounts, shorten URLs, customizable themes and numerous other features.

iPhone Utility Apps

CardStar: Tired of your wallet exploding with all of your various membership and points cards for different retailers? CardStar allows you to enter your membership number for a program and it will generate a scannable bar code you can use when checking out. The app has hundreds of programs already in place, and you can add any that they do not have listed.

Flashlight: This one doesn't need a whole lot of explanation as the name tells you exactly what the app does which is turn your screen in to a flashlight.

iHandy Level Free: Need to hang a picture? With iHandy Level Free there is no more “that looks level†guessing, just whip our your iPhone or iPod Touch and you have an actual working bubble level at the ready any time, any where.

Movies: The Movies app from Flixster allows you to watch trailers for upcoming films, see what theaters near you are playing certain movies, see the showtimes for the movie/theater of your choice and more.

Remote: Control your Apple TV or your iTunes with your iPhone or iPod Touch from anywhere in your Wi-Fi range. This app will let you see the album cover artwork, create new playlists, play with the Genius feature and more.

The Weather Channel: While the Apple devices come with a weather application, it leaves a lot to be desired in the ways of forecasts. The Weather Channel application allows you to look at radar maps, see video of the last weather happenings, get warnings and even more.