In fact, did you realize that many of the best ones are free? Here are our picks for the most useful free apps available.
View financial news, stock quotes, company descriptions, price charts, market trend analyses, and more.
Get up-to-the-minute tracking information on all the packages you've sent or are expecting.
View millions of job listings from thousands of company Web sites and job boards.
Tired of your apps crashing all the time? Use Memory Sweep to free your iPhone's memory before opening up demanding applications.
If you're an Apple MobileMe subscriber, you can use this app to view your online file storage.
Whiteboard: Collaborative Drawing
If you're using your phone to conduct a virtual meeting, use this whiteboard app to create a virtual whiteboard. It works over WiFi or Bluetooth connections.
If you can't make it through the day without your favorite Starbucks drink, you'll love this app. It directs you to the nearest locations.
Drync Wine Free
You won't be confused in wine shops if you've got this handy app. It offers information and pricing for over 1 million wines.
This app plays each note in standard tuning so you can use it as a reference to tune your guitar.
Never be stuck in traffic again. This app offers accurate, real-time information on current traffic conditions.
Save articles you'd like to read on your browser, and then call them up with this incredibly easy app.
Tired of not knowing when your favorite bands are coming to town? With JamBase, you can create a list of favorites and then view a list of local appearances.
MapQuest 4 Mobile
This goes beyond the iPhone's own Maps app with the ability to save routes on MapQuest.com and then view them on your phone.
It's the ultimate guide for any bartender, with recipes for over 7,900 drinks. Check out the Liquor Cabinet feature, which only uses ingredients you have on hand.
NYC Subway Map
Forget clumsy foldable maps; this handy guide puts the NYC subway in your pocket. You can also find apps for other cities' subway systems.
View local restaurants that have open tables and then make reservations through the app.
This will become one of your most-used apps. It turns your iPhone into a wireless remote for controlling your iTunes or Apple TV.
Runner's World Shoe Shop
Let the experts at Runner's World help you find the best shoe for you with these video guides.
Movie lovers, you should absolutely have this on your iPhone. Use it to find movies and showtimes for nearby theaters.
You'll never look up a number for a taxi service again. Just tap a button on Taxi Magic and a car will come for you. It works like magic in over 25 U.S. cities. In over 4,000 other U.S. and Canadian cities, it gives you a number to call.
Waze offers real-time traffic updates created by other Waze users. It also alerts you to police traps, road construction, and more.
This location-based app will tell you about hot local restaurants, movie times, weather forecasts, traffic conditions, and more.
Keep it Organized
This recipe database is great to have while shopping, since it lets you know exactly what items to pick up for dinner.
A Personal Assistant
Keep tracks of your credit card number, bank accounts, cell phone usage, bills, and more with this handy assistant.
AT&T myWireless Mobile
Manage your AT&T Wireless account. Use it to pay your bills, view minutes and data usage, and add or remove features.
It's a one-stop place to record anything, including notes, ideas, snapshots, and audio recordings.
This clever app uses push notifications to remind you of the tasks you need to do throughout the day.
Remember the Milk
This powerful to-do list lets you organize, view, and sort the tasks you need to get done.
Get up-to-date exchange rate information for over 90 currencies and 100 countries.
You'll never be at a loss for words. This app includes 275,000 definitions and 80,000 synonyms.
Here's an app that will save you money every week. Don't fill up your car until GasBag has told you where to find the lowest-price gas.
iHandy Level Free
Is that picture straight? You'll know in seconds with this convenient level.
iHandy Tip Calculator
Some tip calculators are difficult to understand, but you'll love the simplicity of this one.
Travel with confidence with this simple language translator.
This is a great app to have when shopping for plants, since it lets you know about each one's needs before you buy.
Are you worried that your mechanic is ripping you off? This app lets you know what price to expect for car repair or maintenance.
Dictionaries only work if you know how to spell a word, but Speller gives you suggestions for misspelled words.
This GPS-enabled app lets you know about police traps and red light cameras as you approach them.
Convert any type of units quickly with this free app.
This app detects your locations and gives you local listings for businesses.
A Fake Caller
Get out of a meeting or a bad date. This app creates realistic-looking fake calls at any time interval.
Don't e-mail your photos, bump them. This clever app lets you exchange contact info, photos, and more by bumping two phones together.
Access all the Craig's List features directly from your phone. Shop for bargains or post a missed connection instantly.
Free Wi-Fi Finder
Save your monthly minutes; this app helps you find open WiFi connections no matter where you are.
Keeper puts a super-strong, military-grade encryption data vault on your iPhone to protect your personal data.
Looking for a favorite restaurant or store in a new neighborhood? ManGo is a quick and easy way to find your favorite chains.
Mint.com has made personal finance easy, and with this app you can track your budget on-the-go.
If you and a nearby friend have Mover installed, you can exchange images and contact data just by flicking them to each other.
Watch out AT&T, because Skype is here and it lets you make free calls and send instant messages to anyone else on Skype.
The Weather Channel
This app puts the iPhone's default weather app to shame. View conditions for any location, see traffic cams, and get severe weather alerts.