Post by David Pierce. Find me on Twitter.

The “Killer App” is a neat concept. It’s not just apps that are killer, rad or awesome. A killer app is the application or feature that makes you toss out what you’ve already got, buy something new, fight with your spouse over the credit card bill, and giggle all the way to the poorhouse because your new thing is so incredible.

Killer apps vary enormously. When you bought an Xbox 360 even though you already had an Xbox, it was Xbox Live that made you do it.  Of course, you bought the Xbox in the first place because you wanted to play Halo. You bought a smartphone when you already had a perfectly good phone, because this one had the Internet.

For the iPad, the killer app is unclear: is it a gaming console, a netbook, an e-book reader, a TV, or something else? I think the answer, and I’ll grant you that this is a cop-out, is that the killer app for the iPad is its versatility. It’s all of those things and more, rolled into one device.

After a month of using the thing, I’ve got a list of 24 apps that make up the killer app of the iPad. They’re good, they’re even awesome, but the Killer App of the iPad is having all of them, in one place, with me always.

For Fun

Flight Control – You land planes. As many as you can. And then, suddenly, it’s 41 hours later and you’ve missed two days of work.

Words With Friends – Scrabble, that you can play over the Internet with friends and strangers. You get a notification when it’s your turn, and games can take minutes or months. It’s my continual reminder that my girlfriend, even 500 miles away, is much much smarter than I am.

Real Racing – Real Racing is a lot of fun, but it’s also the perfect way to show someone else how cool the iPad is, which is at least 93% of the fun of owning one in the first place. It’s a racing game, and the iPad is your steering wheel.

For Work

Evernote – The iPad app is actually my favorite ever version of Evernote. It’s incredibly attractive, simple to figure out and use, and managing a lot of notes is much better on the iPad than on smaller-screened devices.

Instapaper – I have the biggest crush on Instapaper. I read so much more since getting the app, because I can save everything from news articles to feature stories on it, and read them in fits and starts whenever I get a chance. 20 minutes at a go is a great way to get a ton of reading done.

GoodReader – More and more books are available now in PDF form. GoodReader handles them beautifully, giving you a great interface to read, organize, and share your documents. It also reads Word files, Powerpoint presentations, and much more. When it doubt, a file always seems to open in GoodReader.

Dropbox – All my files. On my iPad. Make a change on my computer, it gets synced to my iPad. I can read, watch, listen, view, and any other verb you can do with files, including save them to the iPad. Having access to all my files in a pinch cannot be overstated in how awesome it is.

Simplenote – As much as I love Evernote, Simplenote is actually a better way to take notes – the application launches faster, it’s a simpler interface, and it doesn’t have any bells and whistles that I don’t want when I’m taking notes in a meeting. When I’m done, I just email the note from Simplenote to my Evernote account, and it’s like it was there all along.

For Media

ABC Player – Pretty basic: all the content on the ABC website (the most recent episodes of most of their shows, plus a lot of bonus content), right on the iPad. It’s my bedtime watching go-to these days.

SoundHound – I can hum a song, play a song, or hear a song on the radio, and SoundHound knows what it is. It gives me lyrics, information, and will buy the song for me, or play a Pandora station based on it. It’s totally a novelty, but it’s such a fun one that I don’t care.

Netflix – More and more of Netflix’s content is available for instant streaming to anyone who gets the $9/month service. All that content is available on the iPad, and will stream right to the device. Lots of movies, even more TV shows, all available whenever I’m bored waiting for the train because it’s 12:30 in the morning and I missed a train by ten seconds and there’s not another one coming for three hours.

Spark Radio – Most radio stations stream over the Internet nowadays. Spark Radio plugs into them all, and gives me an excellent interface for finding them and listening to whatever my little heart desires.

Pandora – I didn’t used to listen to Pandora much, until the day I realized that listening to the Glee soundtrack over and over is only epically fun for so long. After play number 12,385 of “Don’t Stop Believin’,” Pandora became my new best friend. It takes a song, artist or genre, and plays endless music based on it. Great way to find new music, or keep your brain occupied while you work.

Kindle – There’s the iBooks app for the iPad, which is neato-burrito, but I like Kindle better. It’s super-simple, super-fast, and has access to Amazon’s giant library of surprisingly cheap eBooks. Much like Instapaper, I read infinitely more thanks to having all my books with me at all times, and that’s thanks to the Kindle app.

NewsRack – NewsRack syncs with Google Reader, and brings all my news right onto my iPad. I can flip through stories, open and read them right within the app, and with one click send them to Twitter, Facebook, Instapaper, Delicious, and much more. There are plenty of RSS readers on the iPad, so take your pick, but NewsRack gets my vote.

Fluent News – My favorite news source is the Cheat Sheet from the Daily Beast. It’s a daily list of all the most important stories, and a great way to get the news basics in a few minutes. Fluent News is much the same: big stories and news, from the best sources out there.

ScoreCenter XL – “Sports fan” is a mild term for what I am, but even I can’t get through all the information ScoreCenter XL, from ESPN, offers. It’s got news, tons of video, live scores, and all the information to make me feel like I was at the game.

For Life

Night Stand HD – It’s an alarm clock, just a really good one. Multiple alarms, wake up to iPod music, all the bells and whistles. But, when it boils down to it, it’s an alarm that wakes me up. So it’s a keeper.

Epicurious – If there’s ever been an app that can make me cook, it’s Epicurious. It’s got easy recipes, tons of great meal ideas, and infinitely helpful information for chefs aspiring and accomplished.

Sobees – It’s a Facebook client. It’s not perfect, but it gets the job done. And let’s be honest: we all need a Facebook client.

Urbanspoon – If you live in a city full of food choices, or just hate making decisions, give Urbanspoon a whirl. Pick a type of food, a price range, a location, or none of those, and Urbanspoon will find you a place, give you reviews and information, and show you how to get there. I’ve found some great food thanks to the app, and use it whenever my answer to what I want for dinner is “either Chinese, pizza, Italian, or nachos.”

Twitterific – Ditto Sobees, but for Twitter. Some issues, but it works fine, and it’s already moved into my daily routine.

The Weather Channel – Want to know the weather for this weekend? How about three hours from now? How about the weather in Uzbekistan? Or maybe, you want to know how much rain there’s going to be, what the radar looks like, and what on Earth a low-pressure system is? Check, check, check, check, check, and check.

Now Playing – A great app for finding movie showtimes and tickets, as well as watching trailers, getting reviews, and determining what you want to see. It’s the whole movie decision experience wrapped into one application – which is a nice alternative to the indecisive Friday night that ends at 9:30 with everyone going home.

(Bonus because I forgot it before) Corkulous - I love applications that take full advantage of how the iPad looks and feels, and how much of a joy it is to use. Corkulous does just that, creating a giant corkboard that you can move around, add notes and tasks to, and use like a miniature version of a real corkboard. Except it’s way more fun to use, and much more productive too. It’s awesomely visual, and a great way to play with and organize thoughts and ideas.

Okay, there’s my iPad in a nutshell. Having all those on a device that turns on with the touch of a button, lasts forever, and makes people think I’m awesome is pretty killer, if you ask me.

What’s your killer app?

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About the author: David Pierce (1175 Posts)

David Pierce, the founder of Digitizd, is now Reviews Editor at The Verge.