Owners of the $399 iPhone can get a free update, but those with the $299 (8 gigabyte) or $399 (16 gigabyte) iPod touch must pay $20 for their update because Apple tracks revenues differently for iPhones compared with its iPods.

Updates for the iPhone and iPod touch add Web bookmarks to the home screen and a redesigned Maps application that displays a user’s current location.

This week, I’ve been using an iPhone and iPod touch with these updates, and I must say that both devices are much more useful and fun with these improvements. Web clips, or browser bookmarks that take the form of icons on the home screen, give these gadgets a new sense of instant gratification because they direct users to specific Web pages seconds after the device turns on. These little icons can be labeled and moved around, letting you group favorite Web sites on one screen, games on another screen, saved Web research on a third screen and so on.

Getting Synched

Both devices can be updated by synching with iTunes; the iPhone does so automatically and the iPod touch updates only if the owner buys this upgrade through the iTunes Store. New iPod touches include the updated software free.

New to both devices is a redesigned Maps application that, at the touch of a button, displays a user’s current location in an on-screen map — without using Global Positioning Systems. Other non-GPS devices currently do this, but they depend solely on cellphone towers to determine your spot. The iPhone uses both cellphone towers and nearby Wi-Fi hot spots to find your location; the touch uses only the Wi-Fi method.

The iPod touch also now has the same stellar Mail program that is found in the iPhone, a real plus for owners who have been curious about mobile email but weren’t necessarily ready to plunge into a BlackBerry or iPhone, or don’t want to pay for a monthly data plan.

Both devices can store numerous Web clips on up to nine different home screens, each of which has room for 16 icons. A handful of permanent applications appear by default on the main home screen, but these can be shuffled around. Along with Maps and Mail, applications for Stocks, Weather and Notes were also added to the iPod touch.

Multi-touch technology only improves these new features. For example, home screens are easily navigated by flicking a finger horizontally to get from one to the next. Holding a finger on any Web clip causes all of them to jiggle like tiny pieces of digital Jell-O, waiting for you to either delete or drag them around wherever you would like them to stay. Pressing the Home key cements the icons in place.

Trouble Finding Home

But these updates left room for improvement. Maps had trouble on both my iPod touch and iPhone when I asked it to find me in my home in Washington, D.C., and in my office near the White House — the former test circled a 30-block radius while the latter marked me four blocks away. Tests in other locations worked well, and clever “Drop Pin” tools helped me mark and label specific places. But I wouldn’t rely on this feature if I was completely lost and hoping the iPhone or iPod would tell me where I was.

And though I was excited to have email on my iPod touch, this device lacks a speaker and vibrating capabilities, so it can’t chime or buzz to signal newly received email. Because of this, the touch wouldn’t work for me as a serious, everyday tool like the BlackBerry and iPhone.

The free update for the iPhone lets you text message multiple people simultaneously, something the most basic cellphones have been doing for years. But individual responses to these mass texts can’t be seen in the same thread of conversation as that which you started; instead, they generate new text message threads.

On the iPhone and iPod touch, the Maps application now shows hybrid views that combine satellite maps with labeled street names, which are helpful.

The iPod touch is a testament to what can be done on a mobile device without a cellphone carrier’s help. By tapping into Wi-Fi hot spots, which are almost everywhere, I easily checked email, stocks and weather. I had a little more trouble using the Maps application with Wi-Fi because I was more often checking my location while on-the-go in a car or walking.

Collecting Web Clips

I had fun populating the many screens of my iPod touch and iPhone with new Web clips. These are easily added by hitting a “+” symbol at the bottom of any Web page, naming the Web clip and watching it appear on a home screen, often with a colorful accompanying icon like that for AllThingsD.com.

Snapshots of a Web page can be captured and saved in a Web clip by zooming in on a certain section of a page and saving that specific view. This proved helpful when I needed to quickly glance at the Georgetown basketball schedule a few times in one day.

Web applications can be found at www.apple.com/webapps. A game called Ditto involves repeating a pattern on blue, yellow, red and green squares using the touch screen — a digital version of the Simon handheld game. Memory, the old card game, is updated with animated animals on cards. FlyTunes lets users listen to customizable channels from Internet radio, while an app called Floort presents an opinionated topic and asks people to vote on whether they agree or disagree. Even simple Web apps were useful, such as one that turns the screen into a virtual ruler with inches on one side and centimeters on the other.

But it’s good to keep in mind that these are Web applications, and are useless without the Web and/or an AT&T connection.

All in all, Apple’s software updates for the iPhone and iPod touch are exciting, especially because they make home screens much more useful and individualistic. These tiny devices continue to become truly mobile computers.

• Email mossbergsolution@wsj.com.

Digital Cameras

Megapixels: This term describes the highest resolution photo a camera can take. Often mistaken as the most important factor in a digital camera, a high megapixel count — such as 10MP or more — isn’t necessary for the average user unless he or she plans on heavily editing or enlarging photos. Most new digicams offer between five and eight megapixels, which is usually more than enough.

Optical or Digital Zoom: Optical zoom, determined by the physical movement of a lens, matters much more than digital zoom, which digitally alters an image using the camera’s internal computer. Camera companies still try to confuse potential buyers by listing a camera’s total zoom, or the optical and digital zooms multiplied together. Ignore total zoom numbers and instead focus on optical, which now averages around 5x for many new cameras.

Image Stabilization: When generously sized LCD viewing screens started replacing optical viewfinders, they also forced users to hold their cameras at arm’s length, making for plenty of blurry photographs. To remedy this, camera manufacturers have added image stabilization, tools once found only in high-end SLR models. Optical (also called “mechanical”) and digital image stabilization correct for unsteady hands and moving subjects, respectively. Cameras with both types advertise dual image stabilization, which corrects for both situations and costs more.

Mobile Devices

HSDPA and EVDO: HSDPA, or High Speed Downlink Packet Access, is the name for AT&T’s 3G, or third generation, mobile network that operates at roughly the speed of a slower DSL in a home. HSDPA is available in most major metropolitan areas and is seen as the competitor to Verizon and Sprint’s EVDO (Evolution Data Only) networks, though the popular iPhone runs on AT&T’s network using Wi-Fi and EDGE technology rather than HSDPA.

Multi-Touch Technology: Most popularly found on Apple’s iPhone and iPod touch, multi-touch is starting to show up in other products, such as in Microsoft’s Surface, a coffee-table-like computer. Rather than just responding to on-screen touches, this technology enables moving, resizing and zooming pictures and Web pages using one or more fingers simultaneously. Look for many more devices — mobile and otherwise — to incorporate multi-touch in the future.

GPS: Global Positioning Systems are most often found in cars — either built-in or on portable devices from companies like Garmin and TomTom. These gadgets use satellite technology to determine geographic location, and high-end models even display Web content like news and weather along with directions. GPS integration in mobile devices can be used to plot routes in cars, can help users find nearby businesses while on the go and can link friends by showing one where the other is located and what they’re doing.

Digital Music

DRM: Digital rights management is a set of standards that protect the intellectual property rights of online content like music and videos, preventing it from being illegally distributed across the Web. In the past year, Vivendi’s Universal Music Group, Apple and (most recently) Sony BMG said they will start selling DRM-free versions of songs, often for a higher price. In Apple’s iTunes store, these files are called “iTunes Plus” and aren’t restricted like other iTunes content.

MP3: MP3 files are open, without any DRM restrictions. Files that you rip (copy) from your own CDs are usually converted into MP3s, though iTunes users can automatically rip tracks into that program’s special format, called AAC. MP3 files can be uploaded to social-networking sites for sharing with friends and online communities.

These file types are protected by rights that tie them to specific players. Generally, AAC files make up the majority of tracks sold on Apple’s iTunes store and play only on Apple’s iPods; WMA files are Microsoft’s version of proprietary files.

Wi-Fi

The popularity of Wireless Fidelity, or Wi-Fi, brings this technology to more and more portable devices like the iPod Touch and Microsoft Zune and gives companies good reason to incorporate Wi-Fi receivers in new computers — laptops and desktops alike. While available in many flavors, different letters like b, g, a and n stand behind Wi-Fi’s more technical name, 802.11, to help discern one version from another according to characteristics like speed and compatibility. The latest version, “n,” offers the greatest range and speed, and “n” devices are usually compatible with earlier versions.

Televisions

HDTV: High-definition television has now become the standard, capable of displaying vastly better pictures, provided the source is also HD. Today’s more popular flat panel HD televisions are LCDs, or liquid crystal displays, though plasmas still hold their own. Recording HD content can’t be done with a regular digital video recorder; instead, a special HD recorder is required to capture this higher quality content.

480p vs. 1080i vs. 720p vs. 1080p: These numbers refer to the resolution, or sharpness, of a digital display, while “p” stands for progressive and “i” stands for interlaced. A resolution of 480p, known as EDTV or Enhanced Definition TV, is found most often in low-end plasmas or LCD screens. A TV with a resolution of 1080p is currently considered the Holy Grail, and costs the most. But 1080p pictures usually can’t be distinguished from less expensive 1080i or 720p pictures by average viewers at the typical distances from which most folks watch TV.

Blu-ray vs. HD DVD: Blu-ray and HD DVD are incompatible high-definition disc formats that continue to fight a seemingly endless battle to replace the DVD. The Blu-ray camp is led by Sony and the HD DVD camp is led by Toshiba. The two formats aren’t so different, technically speaking, but their very existence is confusing to consumers. The recent decision made by Time Warner’s Warner Bros. to use Blu-ray gives Sony’s side a boost, and now Viacom’s Paramount is rumored to be switching to Blu-ray from HD DVD. Dual-format players from Samsung and LG offer some solace.

Email: mossbergsolution@wsj.com