By MICHELLE PRICE

Microsoft Word and Excel are both applications, but these rather staid and well-established pieces of software are not what modern-day tech enthusiasts mean when they talk about “apps.” The emergence of Web or “cloud”-based IT services and super-smart mobile phone and tablet technology, as embodied by the iPhone and the iPad, has given birth to a universe of weird and wonderful pieces of software brimming with all sorts of information and tools. Apps combine the unique features of the new wave of super-clever hardware, including a camera, a global positioning system, a high-resolution screen, and WiFi capability, with a bottomless pit of Web-based information and data, to deliver some truly innovative and mind-boggling gizmos.

Because apps can be developed by any third party who wishes to try, there are literally millions to choose from.

Apple is preparing to roll out a series of lower-priced iPhones to compete with other smartphones on the market. The new models will run about half the cost of existing iPhones.

Presented here are 10 of the most useful, most recommended and most interesting.

Shazam

This is an application for anyone who has ever heard a song or tune they love on an advert or in a shop but have not been able to identify it. Self-styled as a “music discovery engine,” Shazam is a smartphone application boasting a simple but revelatory function: Hold up the phone to the music, whether the tune is being broadcast from a speaker in a shop, on the TV, or in the gym, and the Shazam application will identify the song and the artist. Users can also view related YouTube videos. Shazam is primarily a smartphone application but it can also be downloaded onto the iPad.

Apple has started manufacturing a new version of its iPad tablet computer with a built-in camera and faster processor. WSJ’s Yukari Kane joins Stacey Delo to discuss.

The Good Food Guide 2011

Foodies of the U.K., rejoice, as Britain’s best-selling and most well-established guide to dining well is available on the iPhone. The Good Food Guide iPhone application, launched last year, includes the entire food guide for 2011, as well as independent reviews of the best restaurants in the U.K. It also allows happy and disgruntled diners alike to upload their own reviews and includes a function, using the phone’s global positioning system and WiFi location service, which allows users to locate restaurants nearby. In addition, users can exploit the handy restaurant reservation functionality, which clicks through to the restaurant website and phone number.

OmniFocus

Always forgetting to pick up your dry cleaning? OmniFocus has the answer. Developed by productivity application specialist the Omni Group, OmniFocus is a location-based task manager founded on the principle that certain tasks are performed in certain contexts. OmniFocus uses the GPS and WiFi positioning capability of the iPhone to organize the user’s list of chores according to their location. For example, if the user has a number of chores to perform in a morning, the OmniFocus app will remind him or her of the tasks when they are in the relevant contexts, such as passing the dry cleaners. OmniFocus also has a sister iPad app.

Drinks Tracker

This application will change your life, but not necessarily in the way you would like. With excessive alcohol consumption costing the U.K’s National Health Service ₤£2.7 billion ($4.4 billion) a year, the health service has developed this handy iPhone app that allows the user to keep track of his or her ongoing alcohol intake. Simply input the strength, size, and quantity of the drinks consumed and the app will tell you the equivalent units and present the information in an easy-to-view graph. This app, if a little depressing at first, is extremely useful for people attempting to cut back on their alcohol intake.

DataVault Password Manager

As more and more applications and IT services are delivered via the Web, consumers are expected to memorize an ever-bewildering array of passwords with an ever-expanding number of characters. Designed by California company Ascendo Inc., DataVault Password Manager offers a handy and intuitive way to store a range of passwords, PINs, credit-card details, and other vital personal information, which is protected with strong encryption technology. The application, which is designed for the iPhone, iPad and iPod Touch, allows users to have all their vital password information safely to hand at all times, although a desktop version is also available.

Find My Car!

Wondering around helplessly trying to find your parked car is a common recurring mid-life frustration dream, but it need never again be a reality with this inspired application. Developed by French mobile application specialist Presselite, Find My Car puts an end to the ignominy of misplacing your car. Using the iPhone location capability, the application allows the user to locate the position of the car and fix it on the iPhone’s map function. For those who have trouble following maps, the application also has the facility to record visual information as a helpful prompt using the phone’s camera. Once the user’s excursion is over, he or she simply follows the map back to the vehicle.

Layar Reality Browser

Produced by Dutch company Layar, Layar Reality Browser is one of hundreds of applications that use a technology known as augmented reality to provide additional information about the user’s surroundings. Augmented reality overlays images, Web links and data on top of the image displayed by the phone’s camera in order to provide useful context-specific information. Hold up the iPhone’s camera to capture the surrounding area and Layar displays a wealth of additional information onto the smartphone’s field of vision, such as the most popular bars nearby, or flats to rent in the area.

IMDb

Whatever happened to the boy who played Oliver in the 1968 film musical? What year was the first Alien film released? The Internet Movie Database (IMDb) has all the answers. As the world’s largest collection of TV and film trivia with a database of some 1.5 million films and TV shows, IMDb can satisfy a vast majority of obscure film-related questions. This app is for any household incapable of finishing a film without squabbling over the name of the supporting actor and other films he has starred in.

Spotify

A good music-streaming application is a must-have for anyone who loves music, whether the app is downloaded onto a desktop, tablet or smartphone. Music-streaming apps allow users to listen to their favorite music on-demand via the Web, without the irritation of endless adverts. There are a number of good streaming applications out there, but Spotify continues to improve and is available on desktops, a number of smartphones, and the iPad. In addition to providing online music streaming, Spotify allows users to play back tunes when offline, and the mobile app offers smooth syncing with the desktop app.

Word Lens

One of the most celebrated apps to be released in recent months, Word Lens instantly translates printed words in one language into another using the phone’s built-in video camera. For example, the user is traveling abroad and cannot understand what a sign says. He or she points the iPhone or iPad camera at the sign, and the English translation will immediately appear on the screen overlaying the initial image using augmented reality. At the moment the application only provides translation between English and Spanish, but the application’s creators—augmented-reality app development firm Quest Visual Inc.—promises more European languages in due course.

Ms. Price is Trading and Technology Editor at Financial News in London. She can be reached at michelle.price@dowjones.com.

Nothing elicits such a strong case of technology guilt as asking other people if they back up their computers. Eyes dart toward the ground. Excuses are made. The subject is quickly changed.

As many people know or quickly find out, backing up a computer can be a painfully slow process. This week, I tested a computer-backup system that requires minimal effort and works in the background to automatically back up files: CrashPlan. This appropriately named program is made by Code 42 Software, a Minneapolis-based company.

CrashPlan is a new software program that takes the hassle out of backing up your computer’s precious hard drive. WSJ’s Katherine Boehret says there’s a range of ways – and a range of prices – to make it happen.

CrashPlan works with all types of operating systems and lets users back up to remote servers in the cloud and/or other computers or hard drives, like another PC they own or one belonging to a good friend or family member (as long as they give permission). The system also sets no restrictions on file size.

On a typical home Internet connection, the backup process to a CrashPlan remote server could take several days or even weeks for a first-time backup. (After that, backups are much faster and happen unnoticed.) The first-time backup for one of my laptops with about 46 gigabytes of data had been running almost continuously for three days when I filed this column on Tuesday. After the initial backup, regular backups won’t take nearly as long. CrashPlan has a mobile app that works on Apple‘s

iPad, iPhone and iPod touch, Android and Windows Phone 7, allowing remote access to backed-up files.

The free version of CrashPlan enables a daily backup to other computers and hard drives but not to Code 42′s remote servers. The subscription-based CrashPlan+ will back up to the remote servers as well as other computers or hard drives. It can back up as often as once a minute and lets users choose what data to back up where.

CrashPlan+ comes in three payment plans, each with its own tiered rates—from a month-to-month option to a four-year subscription. For each of the three plans, the four-year subscription is the least expensive at $70, or about $1.50 a month per computer for up to 10 gigabytes of data; $140 or $3 monthly per computer for unlimited storage; and $288 or $6 monthly for up to 10 computers and unlimited storage. The company offers a free 30-day trial.

I got started by downloading the software to my MacBook, creating an account and starting the initial backup. A scan of my data took a few minutes before the actual backup began. Using my Verizon DSL connection over Wi-Fi, the estimates of how long it would take changed dramatically by the second. I saw estimates of as much as 17.5 days and as little as 6.6 hours.

Katherine Boehret tests CrashPlan, a computer-backup system that requires minimal effort and works in the background to automatically back up files.

I also downloaded CrashPlan onto my office Windows PC, which has a fast, hard-wired Ethernet connection. I logged into my account and opted to back up a folder of photos that was roughly 16 gigabytes. The estimate for this backup was a little over one day, though I didn’t adjust CrashPlan settings to get the fastest transfer on this PC. In a simple menu, I could opt to back up the Windows PC to my MacBook as well as to remote servers—or just to the MacBook alone. On my MacBook, I made sure to adjust the settings to get the fastest speed possible for my giant backup.

Code 42 CEO Matthew Dornquast said the worst-case scenario speeds are initially displayed, but that these adjust down as time goes on. In my experience, the initial estimates didn’t change much.

CrashPlan backs up your newest files first on the assumption those mean the most to you, and it encrypts all files, so file names can’t be read on remote servers or backup computers. I liked CrashPlan’s straightforward user interface because it clearly showed me what my data were doing and where it was being stored. A section labeled “Destinations” let me choose where data was backed up and options included “CrashPlan Central” (remote servers), “Friend,” “Another Computer” or “Folder.” A section labeled “Files” showed exactly what was being stored; in my case, this meant 285,930 files. An “Inbound” section showed any computers that were using my computer for backup.

In settings, users can opt to be emailed or even sent direct messages via Twitter that tell them the latest backup status. This is helpful if you’re only backing up to, say, one other PC in your house and that PC fails to back up.

In addition to over-the-air backups, CrashPlan users with a lot of data, very little patience or both may want to try an alternate option. For $125 (including shipping both ways) and a monthly fee for remote storage, the company will send a one-terabyte hard drive that can be loaded with data and mailed back. Once that huge block of data is initially stored on remote servers, regular backups won’t take nearly as long.

To get data back, a “Restore to Your Door” feature will send you a hard drive filled with your data so you can load it onto a new computer. This also costs $125 (with shipping both ways) and the monthly cost of remote storage.

Compared with competitors, CrashPlan fares well. For example, CrashPlan doesn’t limit upload or download speeds, while Carbonite limits upload speeds for large amounts of data after a certain amount has been backed up, further slowing the process. Mozy supports external drives, but this backup is deleted if the drive is disconnected or turned off for more than 30 days. CrashPlan keeps the backup indefinitely, waiting for the drive to be reconnected.

—See a video with Katherine Boehret on CrashPlan at WSJ.com/PersonalTech. Email katie.boehret@wsj.com.

A version of this article appeared Feb. 15, 2012, on page D3 in some U.S. editions of The Wall Street Journal, with the headline: For Backup, You’ve Got a Friend, Family or Cloud.

By CHAD BRAY

As soon as he was caught, an influential computer hacker agreed to become a government informant and “literally worked around the clock” to help federal agents nab an elusive collective of alleged cyber criminals who have launched online attacks against companies, governments and individuals.

The new details, revealed in court documents made public on Thursday, show how quickly investigators were able to turn 28-year-old Hector Xavier Monsegur against his fellow alleged hackers.

Hector Monsegur’s Twitter profile image.

Known as “Sabu” in hacking circles, he was placed under supervision by Federal Bureau of Investigation agents shortly after he was arrested at 10:15 p.m. on June 7 last year. His file was sealed by a judge.

“Since literally the day he was arrested, the defendant has been cooperating with the government proactively,” sometimes staying up all night engaging in conversations with co-conspirators to help the government build cases against them, Assistant U.S. Attorney James Pastore said at a secret bail hearing on Aug. 5, 2011, according to a transcript released on Thursday.

The investigation led to the unveiling of criminal charges on Tuesday against a group of men allegedly behind Lulz Security, or LulzSec. The group, formed last May, claimed responsibility for a series of brazen online attacks including hacking computer servers of television network PBS in retaliation for a “Frontline” episode about WikiLeaks, and stealing personal information from about 100,000 customers of hacked Sony Pictures.

In addition to the Sony and PBS attacks, LulzSec has claimed responsibility for attacks on the U.S. Senate and InfraGard, an affiliate of the Atlanta chapter of the FBI. Those attacks were all cited in Tuesday’s charging documents.

Mr. Monsegur, a few days after his bail hearing in August, pleaded guilty to 12 criminal charges, including three counts of conspiracy to engage in computer hacking, computer hacking in furtherance of fraud, conspiracy to commit access device fraud, conspiracy to commit bank fraud and aggravated identity theft. He faces up to 124 years in prison. A lawyer for Mr. Monsegur declined to comment Thursday.

On Aug. 10, 2011, a federal prosecutor in Los Angeles who was working on the case asked that details for charges against Mr. Monsegur in Los Angeles remain secret. In a document, Assistant U.S. Attorney Stephanie S. Christensen said other hackers were aware of Mr. Monsegur’s true identity, even though he often used a nickname or online personality while communicating with them. She said if news of his arrest were made public, he might be identified as a cooperator. She noted that the hackers monitored public court dockets.

“The FBI has informed me that the hackers are known to take steps against those who cooperate with the government,” Ms. Christensen said. She pointed to a practice known as “Doxing” where hackers post personal details about a person for public consumption online. “The publicly available information may then be used to harass the cooperator and the cooperator’s family in a variety of ways,” she said. “This obviously creates danger for the cooperator, the cooperator’s family, and law enforcement.”

Prosecutors, who said Mr. Monsegur was kept under close surveillance during the investigation—with software installed on his computer to track his online activity and video surveillance set up in his home—also said that Mr. Monsegur agreed to cooperate at “a significant amount of personal risk” to himself. Mr. Monsegur, who was unemployed at the time, is a foster parent to two nieces.

Some hackers retaliate against cooperators by ordering hundreds of pizzas to their house or calling in hostage situations and having a SWAT team show up, Mr. Pastore said.

During the investigation, Mr. Monsegur, who lived in and worked from a public-housing project in New York City, received information on a day-to-day basis of “upwards of two dozen vulnerabilities” in computer systems from a network of cybercriminals, Mr. Pastore said in court documents released Thursday. The FBI was able to identify more than 150 security vulnerabilities at the time, allowing companies to prevent a hack before it occurred or mitigate harm from prior hacking activity, he said.

Ultimately, federal agents were able to thwart more than 300 attacks that other hackers were planning as a result of information provided by Mr. Monsegur, according to a person familiar with the matter.

LulzSec is one of several shadowy hacker groups that have sprung to global prominence over the past year and are loosely organized, often with no central leadership. Mr. Monsegur is described in charging documents as an “influential” member of three such hacking organizations—LulzSec and two others known as Anonymous and Internet Feds. Charges against a total of six men were announced on Tuesday, after which Mr. Monsegur’s identity was revealed.

—Reed Albergotti contributed to this article.

Write to Chad Bray at chad.bray@wsj.com

A version of this article appeared Mar. 9, 2012, on page B1 in some U.S. editions of The Wall Street Journal, with the headline: FBI’s ‘Sabu’ Hacker Was a Model Informant.

Harry Campbell for The Wall Street Journal

Using a stylus to write by hand on an iPad may make as much as sense as adding a rotary dialer to your cellphone, but there are certain bursts of inspiration that can’t be expressed in touch-typed words. Sometimes, scrawling and sketching is just faster, more comfortable and more fun than tapping virtual keys on a screen.

Fortunately, there are apps that can turn your tablet into the equivalent of a cocktail napkin. And as it turns out, a tablet notebook has some distinct advantages over its paper counterpart. Notes taken on a tablet can easily be emailed, printed and archived to a computer or the cloud. And most notebook apps let you mark up photos—including screenshots. Want to write a pithy note on a Web page and email it to a friend? On an iPad, just take a screenshot by pressing the home and power buttons simultaneously, import the image into your notebook app from the camera roll and notate away. You can do this with anything your iPad screen can display: streaming movies, documents, photos of your cats.

The beauty of the stylus paired with a tablet is that it bridges paper and pixels—the physical and the digital worlds—in which, for the moment at least, we’re all still firmly entrenched.

—Michael Hsu

Take Note: Apps that Turn Your Screen into Paper

Jot! Whiteboard

Jot!

This stellar, easy-to-use sketching app lets you share your page in real time with unlimited users over the Internet. With a free Jot! subscription, collaborators can simultaneously view and update the page from an iPad, iPhone, iPod Touch or a computer running the Safari or Chrome Web browsers. Amazingly, changes are updated across all devices pretty much the moment you lift your pen. This makes Jot! a godsend for brainstorming co-workers or parents on business trips who want to draw a picture with their kids from afar. Each subscriber can host five free sessions per month; blocks of five additional sessions cost 99 cents. $5, available for iPad, tabularasalabs.com

Muji Notebook

Muji Notebook

We don’t value paper for its bells and whistles; we value it for its simplicity. Few companies understand this as well as Muji, the Japanese purveyor of understated housewares, clothing and stationery. Muji carries over its singular aesthetic to the digital realm with aplomb. The app’s beauty is its utter simplicity. The interface is intuitive, clean and calming—just like the app’s paper counterpart. Yet there are hits and misses. Hit: the movable virtual wrist-rest that you can drag around the screen as you write, to keep the side of your hand from confounding your iPad’s touch screen. Miss: The handwriting-recognition feature is laughably inept. Still, the app’s overall elegance prevails. Of all the perfectly capable virtual notebooks I downloaded, this is the one I found myself going back to over time. $5, available for iPhone and iPad, muji.com/app

7notes Premium

7notes Premium

7notes Premium’s ability to convert handwriting into typed text right before your eyes is astounding. The app was somehow able to decipher the odd blend of cursive and block-print writing that I’ve developed over the years and which, until now, only family members and loved ones have been able to read. It even shrugged off my attempts to confuse it with ridiculously sloppy penmanship. Of course, the app isn’t perfect all of the time, but if it misinterprets what you write, a single tap brings up a list of its alternate guesses. Even if you’ve mastered the art of touch-screen typing, 7notes Premium is still nice to have in your arsenal. Penning a personal e-mail by hand can be surprisingly satisfying. $5, available for iPad, 7knowledge.com

Calligrapher

Calligrapher

No matter how pretty you think your penmanship is, writing on a tablet can still make your script look like chicken scratch. Besides the awkwardness of writing on glass, you’ll find the lines you draw often aren’t rendered precisely. The free (ad-supported) and rudimentary Calligrapher app mimics the effect of a Chinese calligraphy brush, but it also works wonders with English words, infusing your computer-rendered handwriting with elegance and character (which, after all, is the whole point of writing something by hand). True, the app may look like it was designed to pen the menus of Asian-fusion restaurants, but it will also make your words of wisdom or pithy notes appear a touch more profound. Free, market.android.com

What Stylus Should I Get?

You can write and sketch on an iPad with your finger, but you’ll find the experience more precise, ergonomic and dignified if you use a tablet-friendly stylus. It’s best to avoid the cheaper models, which feel as solid as a coffee stirrer. At the other end of the spectrum, be wary of high-end PDA styluses sold at specialty pen shops; these often have hard plastic nibs (a holdover from the heyday of the PalmPilot), which won’t work with the capacitive touch screens found on the iPad and most Android tablets.

As a general rule, styluses that are compatible with the latest gear will have a soft tip that gives slightly when you apply pressure. Among these, there are a few standouts. If you prefer the convenience of a ballpoint pen and a stylus in one, consider the Kensington Virtuoso ($18, kensington.com) or the Monteverde One-Touch Stylus ($30, monteverdepens.com). The former is thin, the latter chunky; you’ll know which one is right for you by how it feels in your hand.

And if you’re ready to make the leap to a dedicated stylus, you can’t go wrong with one of Acme’s design-inspired pens (the model shown is based on an Eames pattern) paired with their $16 capacitive tip. This wide-barreled, metal-bodied pen has the heft and balance of a fine writing instrument. If you give up on tablet writing, you can replace the tip to convert the pen to an old-fashioned roller ball. Acme Dots Yellow Pen Set, $130, acmestudio.com

A version of this article appeared Mar. 3, 2012, on page D12 in some U.S. editions of The Wall Street Journal, with the headline: PuttingPentoTablet.