The single best feature in Apple’s second-generation iPhone 3G isn’t the increased speed or the GPS location-finding feature. It is something called the “App Store,” a clever distribution mechanism for third-party programs that can run on the iPhone and on its close cousin, the iPod Touch. And you don’t even need a new iPhone to get the App Store. It is also part of a free software upgrade for older iPhones and a $10 upgrade for the Touch.

Scrabble is just one of the many ‘apps’ available for the iPhone and iPod Touch.

In just the first 10 days since the new iPhone and the App Store launched on July 11, more than 900 programs — applications, or “apps,” in tech jargon — have been introduced by numerous developers. Over 90% cost less than $10 or are free.

Even more noteworthy: iPhone and Touch users have downloaded 25 million copies of these programs, ranging from silly sound effects to challenging games; from news readers to restaurant locators; from social-networking programs to business applications.

We have been furiously downloading and trying out scores of these programs, using a new iPhone 3G, an original iPhone and an iPod Touch, and in general, we are very impressed. We found the process of choosing and downloading apps to be easy and quick, and most of the programs to be useful or entertaining. The vast majority are nicely designed, with great graphics and effective, simple user interfaces.

The easy availability of so many programs written by developers beyond Apple (AAPL) itself makes the iPhone a true computing platform, like a pocket-sized Windows or Macintosh PC. With so many programs already available, and many more in the pipeline, iPhone and Touch owners can have a device with fresh, different capabilities every day.

But the process isn’t perfect. For one thing, it is controlled by Apple, which can theoretically bar a program from distribution or take its time making one available.

There are also some glitches. If you download a lot of apps in a short period, it can slow the phone’s next synchronization with iTunes to a crawl, while iTunes tries to back up all the new programs, each of which can contain numerous hidden files. And there’s a bug in the new iPhone operating system that causes apps to crash, and can even force the iPhone or Touch to reboot, if you use a large number of the new apps in quick succession. Apple says it is working on fixing the latter problem.

Also, Apple’s claim of over 900 programs is somewhat misleading, because more than 100 of those are individual books you can read on the phone.

Apple’s baby isn’t the first smart phone that has attracted developers. Thousands of third-party programs already exist for Nokia (NOK) phones, BlackBerrys, and phones running the Palm (PALM) and Windows Mobile operating systems. But, compared with the graphically rich, snappy iPhone apps — many of which fetch data from the Internet at high speed — the typical program on these older platforms looks positively primitive.

AOL’s AIM program

The App Store can be accessed either from the device itself or from Apple’s iTunes software on a Windows or Mac computer, which then transfers the app to the iPhone or Touch. The programs cover a wide range.

Some fill in obvious holes in Apple’s original complement of iPhone software, things the iPhone has lacked that other phones have. These include AOL (TWX) Instant Messenger, a variety of task and to-do lists, sophisticated note takers and a voice dialer. There are numerous versions of popular board, card and word games, like solitaire, mahjong, Scrabble and Sudoku. There are also eye-popping iPhone versions of popular video games, some controlled by the phone’s motion detectors, which allow you to move cars and characters by just tilting the phone.

Numerous programs let you perform Internet functions without using the Web browser on the iPhone or iPod Touch. These include news readers, Internet radio players, sports-information apps, and programs that let you blog or use Google (GOOG) or Facebook or MySpace.

There are business programs from Oracle (ORCL), Salesforce.com and Bloomberg. And there’s a clutch of Bible programs.

Some are simply goofy, like a virtual Star Wars-like lightsaber, a rotary-phone dialer and a virtual “stapler.” And several programs turn the phone into a flashlight for emergencies.

There are way too many interesting apps to review here, but these are some we liked, in no particular order.

AOL Radio

AIM: free

This version of AOL’s popular instant-messaging program does a competent job with text chat, though it can’t yet do video or audio chats, or transfer files. Because Apple isn’t allowing third-party programs to run constantly in the background, you can’t receive new messages in AIM while doing other things. This will supposedly be fixed by new Apple technology due later this year.

AOL Radio: free

While the iPhone and Touch contain full, terrific iPod capabilities, they don’t come with Internet radio players like this one. It can stream music and talk from a wide variety of online sources, including the Internet versions of broadcast radio stations.

Evernote: free

This is an elegant note-taker that has been on computers for a while. You can jot down text notes, store photos or dictate audio memos. And it synchronizes with your Evernote account on Windows or Mac PCs or the Web.

Instapaper: free

A handy way to store Web pages on your iPhone or Touch for reading when you’re offline. While on your computer, an Instapaper button added to the Web browser can snag Web pages for your personal Instapaper database. Then, when your iPhone or iPod Touch is online, it synchronizes with the Web-based Instapaper database. Later, when you’re offline, the pages are still there on the device, ready to read.

Travelocity TravelTools: free

You can use this to check flight schedules, gate assignments and security waiting times. While you can’t book flights through this app, there’s a button that automatically calls Travelocity’s toll-free booking line.

More Cowbell!: free

This is inspired by the Christopher Walken/Will Ferrell Saturday Night Live skit, which made the lowly cowbell a cult musical instrument. Whenever you tap the on-screen cowbell, it makes the recognizable, hollow sound heard in songs like “Down on the Corner,” by Creedence Clearwater Revival. You can play along with any song you choose on the iPod Touch or iPhone.

Touch Tarot: $0.99

Touch Tarot

Touch Tarot is a digital tarot-card reading that takes place on your iPod Touch or iPhone, instead of at a table inside an incense-scented tent at the county fair. Phrasing above each card tells its general category, and below each card is a brief explanation of its meaning. For example, we turned over the Wheel of Fortune card in one card reading, and it said, “Advancement for good or ill. The unexpected may occur. Good fortune.”

iWant: free

The iWant app displays 12 black-and-white icons on your device’s screen, each representing a different category of something you might be looking for — including restaurants, bars, cafés, hotels, drugstores, banks, car rentals and movies, among others. The device identifies your location, and each category can be tweaked to search by distance or highest rankings from Yelp, a user-written rating service.

Urbanspoon: free

Urbanspoon resembles a slot machine: From left to right, columns show the location, cuisine and cost of nearby restaurants. Instead of pulling a lever to start the slot machine, you simply shake your iPhone or iPod Touch whenever you want to find a restaurant. When it stops, you see the name of a restaurant near you and its classification in each category. (You can also specify what location, cuisine or cost you’re looking for.)

Air Hockey: $0.99

Air hockey works like the game you used to play in your best friend’s basement. You play against the computer, using a fingertip to push red or blue mallets that move a puck around the screen-turned-table and trying to sneak the puck past your computer opponent to score a goal.

MotionX Poker: $4.99

MotionX Poker

This is an addictive poker game, played with realistic, beautifully rendered dice instead of cards. The cool thing is that you roll the dice by simply shaking the iPhone or iPod Touch; convincing sound effects accompany each roll of the dice.

MLB.com At Bat: $4.99

There are lots of cellphone apps and services that can give you live updates on baseball games. What’s special about this one is that it adds video clips of key plays that you can view while the games are still in progress, using the full power of the gorgeous screen and video player on the iPhone and the Touch.

Crash Bandicoot Nitro Kart 3D: $9.99

This is a rollicking, fun iPhone and iPod Touch rendition of the classic video racing game, where you control your car by tilting the phone. The graphics are good, and the game-play is responsive.

Truphone: free

This is the first app for the iPhone that allows you to make cheap phone calls over the Internet instead of using the built-in cellphone capability, which can be much costlier, especially for international calls. In our tests, we had some trouble at first, but after we removed and re-installed the program, it worked fine. Calls to 40 countries are six cents a minute to landlines and 30 cents a minute to cellphones. The iPod Touch lacks a microphone, so this app works only on the iPhone.

Write to Walt and Katie at mossbergsolution@wsj.com

This week, I gathered up some useful shortcuts that come built into most of the BlackBerrys, even older models, made by Research In Motion Ltd. but not many owners actually use or know about them. Ironically, most of these shortcuts are conducted using a BlackBerry feature that the iPhone lacks: its physical keyboard. (The iPhone uses a virtual keyboard that appears on-screen only when needed.)

Some useful shortcuts are built into most BlackBerrys, even older models, though not many owners actually use or know about them. Most of these shortcuts are conducted using a BlackBerry feature that the iPhone lacks: its physical keyboard.

Some of these shortcuts are seemingly obvious, like number or capitalization locks, but others are more obscure, like codes that can be entered to display the BlackBerry’s precise signal strength. Some shortcuts are performed with a single keystroke; others work in conjunction with a trackwheel or trackball, depending on your BlackBerry model, and still others work when two keys are pressed simultaneously. BlackBerrys with condensed keyboards that use auto-correcting SureType may require extra or different keystrokes.

Navigation Simplified

A series of keystrokes work in various BlackBerry applications to make navigation much faster. Pressing the Space bar works like Page Down on a computer keyboard, moving down one screen per press. Holding Shift while pressing the Space bar moves in the opposite direction, like the Page Up key. To quickly move to the very top or bottom of a page, press “T” or “B,” respectively. Another way to page down or up through lists is to hold the ALT key while scrolling with the trackwheel.

Users can toggle between the BlackBerry’s running applications without the extra step of navigating back to the Home screen. To do this, press ALT and the Escape key, then release Escape and use the trackwheel to scroll through a display of icons that represent running programs until you reach the desired program, then release the ALT key to select that program.

Messaging Magic

Shortcuts in BlackBerry messaging can be a real boon when you’re trying to get work done quickly. While looking at a list of emails, hit “C” to immediately start composing a new email. When a specific email is highlighted, pressing “R” will reply to that message; “L” will reply to all and “F” will forward it. Hitting “J” while an email is highlighted will jump directly to the oldest message in that email chain.

A list of emails can be more neatly organized from the message screen by holding the ALT key and pressing a letter. “I” will alter the list to show only incoming emails, “O” will show just those emails that were sent. “P” shows a phone log, including dates and times, and “s” displays all SMS messages made or received on the BlackBerry.

In the body of a message, pressing the Space bar twice inserts a period and capitalizes the next word. When the left Shift key and ALT are pressed together, the keyboard’s number lock is on; the right Shift key and ALT work as the caps lock. Holding any letter down will capitalize it, saving users from pressing another key to do so. To type a letter with an accent, hold the letter key down while scrolling up or down with the trackwheel until you find the correctly accented letter.

Type Less, Say More

While composing emails, a series of AutoText codes can be typed in the email body to automatically display certain phrases or information. Typing “mynumber” and a space in the text of an email will automatically display your BlackBerry’s phone number. Similarly, when “LD” is entered the local date is displayed, and when “LT” is typed the local time appears.

If your email inbox is full and you can’t send emails, find out the PIN of your recipient’s BlackBerry and use it to message the person directly. (To find your own PIN, type “mypin” and a space into the body of an email. This code can be used to send PIN messages from one device to another without using the device’s usual email system.)

Geeky Codes

If you’re just dying to know some techie details about your BlackBerry, the “Help Me!” screen will be right up your alley. To view the “Help Me!” screen, press ALT, Shift and “H” simultaneously. This displays data that won’t matter much to the average person, such as the device’s vendor ID, platform and free file space. But it also shows the exact percentage of remaining battery power on the BlackBerry, which could be helpful if you aren’t sure how to interpret the imprecise battery indicator bars at the top of the home screen.

Another way to geek up your BlackBerry is to change its signal strength indicator from bars to numbers that tell how many decibels per milliwatt the device is transmitting. To do this, go to the Home screen and hold down the ALT button while typing “NMLL.” My BlackBerry displayed a minus 75 when I made this change. Strengths of minus 50 to minus 90 are said to be good, while anything higher, like minus 100, isn’t. Though this numerical indicator won’t likely be of any practical use, you could use it to turn to a friend and compare reception during an excruciatingly boring meeting.

One way to impress a technophile on a date is by pulling up a BlackBerry’s Event Log. To do this, go to the Home screen and hold down ALT while typing “LGLG.” This retrieves a long list of numerous confusing codes representing the functions that were performed on your device. The Menu screen in the Event Log gives users the option to clear this log, freeing up some BlackBerry memory, while an Options screen lets people set the log up to record only certain kinds of activities.

Finally, to reboot your BlackBerry without removing its plastic back and taking out the battery, press ALT, Right Shift and Delete simultaneously. More codes can be found in the blogosphere or in a special section of RIM’s Web site: http://na.blackberry.com/eng/support/blackberry101/tips/. Adopting just one of these shortcuts can significantly change the way you use your BlackBerry.

Edited by Walter S. Mossberg

Write to Katherine Boehret at mossbergsolution@wsj.com