A: That’s right. It’s a characteristic of Android, the Droid’s operating system made by Google, and it’s something I noted as a weakness when I reviewed the first Android phone over a year ago.

Even though the Droid comes with 16 gigabytes of memory, in the form of a removable card, apps can’t be stored on this memory card. They must be stored in a special area of internal memory, which in the case of the Droid totals only a measly 256 megabytes, about a fourth of one gigabyte. The memory card is reserved instead for things like documents, music, videos and pictures. That limits the total number of apps the phone can hold at any one time.

Google says the amount of internal memory allotted for apps is up to the hardware makers, and notes that the Droid has twice as much as the original Android phone. It also says that makers of complex apps that use things like graphics that are ancillary to the core app itself could theoretically offload these files to the memory cards.

But users of Apple’s competing iPhone can devote nearly all of its 16 gigabytes of memory to storing third-party apps, allowing many more apps to be stored on the phone.

I have all my data (addresses, calendar, notes) stored on my Palm Zire. I’d like to get an iPod Touch, but can’t figure out how to transfer the Palm calendar. Can you help? Or, do you know of any other “smart” handheld that will allow me to import my Palm data and give me Internet/email access?

A: There are various workarounds for doing the transfer to an iPod Touch, but, since you ask, there is another smart phone with great Internet capabilities that comes with a way to do it simply and directly: the Palm Pre. It’s based on a new and different operating system than your Zire is, called webOS, and is designed to sync with wireless contact and calendar sources rather than desktop programs.

But Palm has developed a one-time, one-way utility for transferring data from desktop software used by an older Palm to one of the wireless calendar and contact services with which the Pre was designed to sync. More information is at: http://bit.ly/2ivFI.

I want to buy a new computer and I really like the new iMac with the 27″ screen. I am 72 years old, which is one of the reasons I want the larger screen. Please tell me if you think my buying this iMac is a good idea. Is there some negative aspect of the iMac that I should be aware of?

A: I gave the new iMac with the huge screen a positive review, so I obviously think it’s a good computer. But, if by mentioning your age you mean to imply that you have vision issues, you should be aware that the new iMac’s screen isn’t just physically large, but is high resolution.

That allows it to pack a lot more content onto the screen, but, depending on what program you’re using, it can make the text small. Word processors, email programs and Web browsers usually allow you to enlarge text, but not all programs do.

The Mac itself has a system-wide zooming feature, but that makes some tasks harder to work with. I recommend you go to a store and play with the big iMac for a while to make sure you feel comfortable with its screen resolution.

You can find Mossberg’s Mailbox, and my other columns, online for free at the All Things Digital Web site, http://walt.allthingsd.com.

I am utterly fascinated with the iPhone. Dying to get one. I’ve been a Verizon Wireless person for 15 years and have never had a coverage problem in the metro Boston area. I don’t hear great things about AT&T’s 3G. Do you think it’s worth the switch?

While I believe the iPhone is a marvelous device, I have always advised that nobody should get any phone unless it is on a network that they are sure works to their satisfaction in the areas where they will use it. Personally, I find AT&T’s network adequate where I use it, and getting better, so I am happy with my iPhone. But there are many others who have either given up their iPhones out of frustration with AT&T, or who have decided against buying one because they prefer another carrier, or want to avoid AT&T.

So, my advice is to ask friends around Boston who have iPhones or other AT&T 3G devices how they feel about the network. You might also enter your ZIP Code at some Web sites that track overall carrier coverage and dead zones, like cellreception.com, or deadcellzones.com.

If this research suggests you should avoid AT&T, but you are still “dying” for an iPhone, you might consider the iPod Touch, which is essentially an iPhone without the cellphone inside. It lacks the iPhone’s camera, GPS and built-in microphone, but it does connect to the Internet via Wi-Fi and runs the vast majority of iPhone apps. It doesn’t carry any monthly fee or require a carrier contract.

How do I forward an email from Gmail? I don’t see any icon for forwarding messages like I do on other email programs.

Gmail hides a bunch of menu choices under the Reply icon in the upper-right-hand corner of open emails. If you click on the small downward arrow next to the Reply icon, you will see more actions you can take on the message, including Forward, Reply to All, Print and others.

I read your recent article on IE8 and installed it on my desktop. I did not notice in your article any mention of IE8 slowing the computer down significantly, but it has had this effect on my PC. Why didn’t you mention it? Can I uninstall IE8 and return to the prior version?

I didn’t mention the problem you are having because I never observed that Internet Explorer 8 caused any general slowdown of any of the multiple Windows PCs on which I tested it. I did warn that IE8 itself grew sluggish when it had a large number of Web sites open simultaneously in tabs, but, in my tests, even that didn’t slow down the whole computer.

However, you can indeed uninstall IE8 and return to the previous version. Microsoft has provided complete instructions, and even an automated uninstall program, at: support.microsoft.com/kb/957700.

• You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

I get confused by all the different models of the BlackBerry — Bold, Storm, Curve, Pearl and so on. Can you briefly explain the differences?

There are too many models to list here, because RIM, the maker of BlackBerry, makes varying versions for competing wireless carriers, and these may have different features, even if they look the same. However, here’s a quick breakdown of the main flavors.

The Bold is the top-of-the-line BlackBerry, relatively large and costly, with a wide keyboard and a big, vivid screen. The Curve is its little brother — still sporting a good, full, keyboard, but lower-priced, smaller and lighter. The newest Curve, called the 8900, has a beautiful screen and is even sleeker than its predecessor.

The Pearl is a slimmer, low-priced, more fashion-oriented model with a truncated keyboard that has two letters on each key and relies on software to guess which one you meant to hit. The Pearl Flip is much like the Pearl, except, as its name implies, it’s a flip phone.

The Storm is the BlackBerry line’s most direct competitor to the Apple iPhone. It’s the only BlackBerry without a physical keyboard, instead relying on a large, beautiful touch screen for typing and navigation. Unlike on the iPhone, however, the Storm provides physical feedback each time you press down on the screen.

I’d be interested in the new, tiny iPod Shuffle, except that I dislike Apple’s earbuds. And, because they have now moved the playback controls to the earbud cord, I can’t use my favorite third-party set. What are my options?

Well, one option is to buy the old model of the Shuffle, which Apple is keeping on the market. It’s larger, but still very small, and has the controls on the player itself, rather than on the earbud cord, so you can use plain old earbuds or headphones from other companies. Plus, at $49, it’s $30 less, though it has only 25% of the capacity of the new one and lacks the new model’s voice features.

Another, costlier, option is to buy better earbuds that have the new controller built in. Apple sells a pair of $79 in-ear buds with a control module on the cord. They were designed for the iPod Touch, but the company says they work perfectly with the new Shuffle. Several other headphone companies, such as Klipsch, have announced plans to offer either headphones or adapters with Shuffle-compatible controls in coming months.

Is it safe to upgrade my Vista PC to the beta version of Windows 7?

Since it is a beta version, there is always some danger of problems. But I have upgraded a couple of Vista computers with no special tricks or help, and with no significant problems. Still, there are a couple of caveats. First, Microsoft will be replacing the beta with a more polished “release candidate” that could involve a re-installation process, so you may want to hold off. Second, Microsoft isn’t guaranteeing that every hardware feature on every computer or peripheral will work properly under the pre-release versions.

• You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

Is there a way to transfer a Windows Media music file to iTunes?

If the Windows Media file is copy-protected, typically because you bought it from an online store that copy-protects its music, iTunes cannot import or play it. However, if it is unprotected, which is typical for files you created from your own CDs using Windows Media Player, iTunes can import the file and automatically convert it into a format it can use.

I would like to purchase an iPhone, but run it on the Verizon network. I realize that AT&T has an exclusive at this time, but is there a way to do this on the secondary market?

No. The radio inside the iPhone is incompatible with the network technology used by Verizon and Sprint. That cannot be changed by hacking the software, or replacing the SIM card in the phone.

I need to buy a new laptop computer and am wondering if you think Vista is wise at this point or should I still stick with Windows XP if I can find it? I only do emails, browsing the net and some downloading of music and photos. I am retired and don’t know much about computers.

Vista easily handles the tasks you want to do, but it will require heftier hardware to work at acceptable speeds, and, assuming you are used to working with XP, Vista will require you to learn some new things. If you buy XP, you can get away with a more modestly equipped computer, and you will be working with a more familiar interface. So, in your particular situation, I would suggest an XP machine. But I urge you to make sure it gets upgraded to the latest revision, called SP3, which bolsters the security of XP, so it is closer to that of Vista. Depending on your setup, this upgrade may be delivered automatically by Microsoft, but you may have to agree to accept it.

You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

A friend of mine suggested that I “defragment” my computer every once in a while. He says it will boost performance, but he also said it will move my data around. I tend to be very organized as to where I put documents on my computer. Will defragmenting my computer jumble my files and put them into random places?

No. Defragmenting a hard disk doesn’t change or scramble the organization of files and folders that you have established. Your file organization should look just the same after defragmenting the disk. What defragmenting does is rearrange the location on the disk of the data segments that make up your files. In some cases, a single file like a word-processor document might actually be made up of multiple data segments, invisible to you, that are located in widely separated physical spots on the disk. Defragmenting tries to optimize the location of these segments so that the computer operates more efficiently.

I saw your review of Norton Internet Security 2009, and wonder what is the difference between this product and Norton 360?

Norton 360 has the same features as Norton Internet Security, but adds some additional ones, like online backup and PC “tune-up.” It also costs more. However, the current version of Norton 360 doesn’t include the improvements I wrote about in the NIS product that make it faster and less of a burden on your computer. Those are planned for a future version of Norton 360.

Can I use one of the new 3G iPhones as a wireless modem for my Apple laptop?

No. That function isn’t built into the iPhone and Apple yanked from distribution a third-party program that enabled using the phone as a modem. I suspect the reason is a business one, not a technical one. Cellphone carriers like AT&T typically take the position that connecting a laptop to their networks, whether via a data card or via a cellphone used as a modem, should command a higher monthly data charge than they typically levy for a cellphone alone.

You can find Mossberg’s Mailbox and my other columns online free at the All Things Digital Web site, http://walt.allthingsd.com.

I recently lost my cellphone for a few hours. What was most upsetting was that I have nearly three years of family photos stored on my phone’s memory card. Other than emailing all of these photos to myself and then saving, is there any way you can think of how I can move these en masse (over 100 pictures) to a hard drive or disc?

Well, assuming the card is removable, you can simply remove it from the phone, pop it into your computer, and copy the pictures to the computer’s hard disk. Depending on what slots your computer has, and the type of memory card the phone uses, this might require using a cheap, small adapter for the computer.

This should work with any modern computer, Windows (MSFT) or Mac (AAPL), and no special software should be required. The memory card should show up as an external disk drive, and you would just open the folder or folders containing the images and copy them to a folder on your hard disk, as you would with any other file. You can leave the originals on the card if you wish. Alternatively, you could import the pictures using photo software like the Vista Photo Gallery or Apple’s iPhoto, although you will want to be sure that the photo software is set to save a duplicate of each photo on the hard disk.

I read your column about avoiding identity theft last week, but am still concerned. I look at my T. Rowe Price (TROW) account, my Chase account, and my J.P. Morgan (JPM) account every day. I also pay my bills online. Is it safe to do this? I am afraid someone will try to steal my passwords and get my money.

There is nothing wrong with checking your accounts and paying your bills online. Millions of people do that safely. All I was saying last week is that there are some rules you should follow to avoid falling into traps commonly set by crooks. One important rule is to never, ever trust any email you get purporting to be from a financial institution, even if it looks official. Never click on any link in any such email, or enter any login or account information in such an email.

Beyond that, just log into the sites manually or using bookmarks you created yourself. Keep your login IDs and passwords for these sites safe, either by memorizing them or writing them someplace where they won’t be easily seen or found. Choose passwords that are hard to guess, and change them every so often. I would also advise against checking financial sites or doing online banking when on public networks, especially wireless networks at hotels, coffee shops, or airports, because some crooks monitor what is typed on such networks.

What exactly was Microsoft’s thinking in moving from XP to Vista as its operating system? If it was for improved resistance to viruses and phishing, I can accept the slower operating speeds along with the few other glitches.

As with any new operating-system project, the development of Vista had numerous aims, including easier networking and an improved user interface. However, Microsoft officials at the time repeatedly said that much more robust security was the main design goal for Vista. And, in fact, Vista does have an array of security features Windows XP lacked. However, much of the antiphishing work is contained in version 7 of the Internet Explorer Web browser, which is also available to XP users. And Vista didn’t eliminate the need to operate add-on security software.

It’s also worth noting that Microsoft is continuing to bolster the security and other features of Windows XP, and will soon release a major XP update called Service Pack 3, or SP3. It includes improved security.

• You can find Mossberg’s Mailbox, and my other columns, online for free at the new All Things Digital web site, http://walt.allthingsd.com.

Last week, when you wrote about the ChaCha cellphone search service, you didn’t say how they make money. Are they collecting phone numbers from customers so they can send spam text messages, or sell the numbers to others who will do so?

ChaCha allows you to ask any Web-searchable question, by speaking it or texting it over a mobile phone, and then it sends you the answer via text message. The company charges consumers nothing, but says it is hoping to make money by striking deals with cellphone carriers to incorporate the ChaCha service into their current 411 phone-number look-up services. Also, it hopes to eventually include ads in the text message answers it provides.

In addition to the message that includes the answer, ChaCha sends you a message saying it is working on your request and restating your question, so you can see if it understood you correctly. It also sends an introductory text message to first-time users and occasional tips on how to use the service. Scott Jones, ChaCha’s chief executive, asserts that “we do not spam” and “we never make phone numbers and/or email addresses available to others.” He said the company is updating its privacy policy to make that clearer.

We have DSL service. I use several Web-based applications, one of which is online backup, and my husband is concerned that they degrade his use of the Web, which includes creating Web sites. I contend that that is like saying turning on one light bulb is using too much electricity, that two people on one DSL line aren’t using up too much bandwidth. Who is right?

Every situation differs, depending on exactly which programs you are each using, how you have them set, whether you are using them simultaneously, and how fast your DSL connection is. However, in general, your husband is correct that it is possible for heavy Internet usage on one computer in a home to slow down Internet speeds on another.

This is especially true with something like online backup, because it relies on your DSL account’s upload speed, which is typically far slower than the download speed. If your online backup program is trying to push a bunch of files over a slow upload connection, while he is in another room trying to upload new versions of a Web site over the same narrow upload pipe, it could affect the speeds he gets. You might try coordinating or staggering those online activities that involve heavy uploading. Normal Web surfing or emailing shouldn’t require any such coordination.

I am thinking about purchasing a Dell (DELL) XPS One all-in-one desktop, but I have one question. Does the Dell’s built-in TV tuner require any extra attachments to watch TV right out of the box?

You can watch over-the-air stations and analog basic cable stations right out of the box, without added equipment. However, you may want to connect a small desktop antenna to improve reception, which is what I did when I tested this machine. To use the XPS One with digital or premium cable or satellite stations, you would have to connect it to a cable or satellite receiver, just as most people do with their TV sets. This requires the use of an adapter that comes with the machine.

• You can find Mossberg’s Mailbox, and my other columns, online for free at the new All Things Digital web site, http://walt.allthingsd.com.

I am considering the purchase of the MacBook Air (AAPL). If this computer freezes up, as my current Dell Inspiron does on occasion, how would I correct for that? I usually remove and then replace the battery on the Dell (DELL). But what would I do if this happens with the Air, since it has no removable battery?

You can force a frozen MacBook Air — or any current Mac laptop — to shut down and restart without removing its battery. You just hold down the power button for a few seconds until the machine shuts off, then wait a few seconds, then turn it on again.

I am a Verizon (VZ) customer and have a Palm (PALM) Treo 700W for personal use. I would like to replace the Treo but, in light of Verizon’s announced “open network” policy, I am wondering if this is the right time.

It’s far too early to know what new phones will be available under the new Verizon program, since that depends on which phone makers decide to make devices to run on the “open” network, and what kinds of devices they might produce. There is the potential for phones that are more creative or interesting than what is available today, but it’s only a potential. Verizon has just laid out the first details of the plan, and no product announcements are likely for quite a while. If your Treo needs replacing soon, and you want to remain a Verizon customer, you will have to choose from the company’s current smart-phone offerings.

Are there any cellphones that allow for two separate phone numbers? Right now I carry two devices, both with the same carrier.

At least in the U.S., each cellphone, or each SIM card that goes in a phone, is normally tied to a single number. To use two numbers on a single phone, you could purchase an unlocked phone running on a GSM network and then purchase two SIM cards, each with a separate number, and swap them in and out. But that would be an inconvenient process, since inserting and removing SIM cards typically requires opening the phone and even removing the battery.

You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

Q. Is there any way to watch high-definition TV on a Mac in real time — not downloaded from a service?

A. As on Windows computers, there are add-on TV tuners for Macs that can both receive and record TV programs in real time. Some of them can handle high-definition programming. The best-known company that sells such tuners for the Mac is called Elgato, at elgato.com.

Q. I’m interested in your perception of the Treo’s future. I currently use (and generally like) a Treo 650. I’d like to upgrade, but I’ve read recently that Palm’s future is uncertain. I wonder if you think the Treo is on a slippery slope down, while the Apple iPhone will likely improve.

A. I do believe that Palm has allowed its software to stagnate and hasn’t moved fast enough to make its hardware thinner and cheaper. However, there are also some positive signs at Palm. Its new Centro phone is pretty good, smaller and less costly than a Treo. And the company is receiving an influx of funds and talent from a group of outside investors with experience at Apple, among other places.

Palm’s fate and future may depend on the success of a project it has undertaken to create an entirely new operating system. But the outcome of that effort won’t be known for quite some time.

The iPhone, which is already very good, will likely get better, as it is just at the beginning of its life. It has raised the bar for other smart-phone makers, such as Palm, especially when it comes to software. But I expect other companies to match at least some of the iPhone’s features and style, which means Apple will have to hustle to keep its lead. In the past five years, Apple has done very well at staying ahead of competitors in the design of its computers and portable music players. But the cellphone business is full of companies with more imagination than the typical PC maker and more resources than many makers of portable music players, so the challenge for Apple will be greater.

Q. My mom is legally blind and has difficulty working with email and downloading files. I try to help her by phone, but it never works, and we live far apart, so I can’t just go over to help her. I would like to install an application on her PC where I can take over remotely from home. Do you have any suggestions for this type of application?

A. There are a number of possibilities. One very simple option is a program called CrossLoop, at crossloop.com. Some versions of Windows, such as Windows XP Professional and Windows Vista Ultimate, also have remote desktop control built in.

You can find Mossberg’s Mailbox, and my other columns, online for free at the new All Things Digital Web site, http://walt.allthingsd.com.

Write to Walter S. Mossberg at mossberg@wsj.com

Here are a few questions about computers I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability. This week my mailbox contained questions about using an iPhone overseas for data purposes, running Microsoft Office 2000 on Vista and using broadband-provider email in two locations.

You recently wrote that iPhone owners using the device overseas must roam on AT&T at high rates, because the iPhone won’t work with SIM cards from foreign carriers. You noted that AT&T has a monthly plan that cuts these per-call voice rates somewhat. But what are the options for using an iPhone overseas for data purposes, such as email and Internet browsing?

Until Apple initiates iPhone service with foreign carriers, which is expected to be a gradual process that will begin in Europe, iPhone owners traveling abroad will be forced to roam on AT&T and to pay through the nose for data as well as voice calls made over cellular-phone networks. They won’t be able to buy cheaper service from a local foreign carrier and enable it by simply replacing the phone’s AT&T SIM card with the local carrier’s.

In addition, it is important to note that, even if you are willing to swallow these huge voice-and-data rates, you must call AT&T (formerly Cingular) before you leave the U.S. with your iPhone (or any AT&T phone) to modify, or “provision,” your calling plan so it will even work overseas.

Here are the details. Note that these prices and plans apply to many other phones AT&T sells, not just the iPhone.

To recap the voice-calling situation, AT&T charges very high fees, which can be mitigated a bit by adding a special $5.99 monthly add-on feature, called AT&T World Traveler, to their plans. This voice feature allows you to roam in 190 countries and gives you discounts on calls from 80 countries. For instance, in France, Italy, Germany, and Britain, you pay a still-high 99 cents a minute, compared with an even worse $1.29 without the plan. In Hong Kong or Israel, you pay a whopping $1.99 a minute, instead of an even more outrageous $2.29 or $2.49, respectively, a minute.

For email and the Web, the best bet for iPhone owners is to avoid using cellular networks and employ the phone’s Wi-Fi capability, which can cost nothing extra. Try to find a free or reasonably priced Wi-Fi hot spot in which to check email and do Web browsing. You may even be able to make cheap voice calls this way using Internet-based calling services like JaJah (mobile.jajah.com) which, in my domestic tests, worked properly via the iPhone’s Web browser.

However, if you need to check email constantly or frequently, you are unlikely to be able to depend solely on the Wi-Fi method. You can rely on AT&T roaming to do this over foreign cellular services, but, as with the voice call situation, it will cost a fortune.

AT&T offers an add-on plan for $24.99 a month, called the “PDA/Smartphone/iPhone International Data Plan.” This is on top of the $5.99-a-month voice plan, and is also additive to the $20 a month for unlimited data when in the U.S. that is built into your base plan. But it isn’t unlimited. You get only 20 megabytes of overseas data use a month, and pay a stiff $.005 a kilobyte for all data use above that.

Plus, this international-data plan only works in 29 countries. Outside those countries, the cost is an astounding $.0195 a kilobyte, or roughly $20 a megabyte. To put that in perspective, a single email with a medium-resolution picture attached could amount to a megabyte. More information is at www.att.com/wirelessinternational.

One more note: apparently AT&T can and will cancel your roaming service overseas if it notices what it considers an unusually high number of calls being made. One reader with an iPhone reported that, after arranging belatedly in Europe to get the voice-roaming service, he was suddenly cut off when he reached India, with AT&T explaining the cutoff as an attempt to prevent suspected fraud.

According to this reader, AT&T said he had been cut off “because there were ‘too many calls from India and other countries’ and they did not think it was possible anyone could be doing that for real, so to protect me, they cancelled the service.” An AT&T spokesman says the company can’t comment on the details of this particular case without knowing the traveler’s phone number.

You say Office 2003 runs OK on Windows Vista. I have been using Office 2000 and it does everything I need. Will it also run OK on Vista?

Microsoft doesn’t officially support Office 2000 on Vista. It may work, but I haven’t tested it.

Is there a way that I can use my same email address both at my home in New Jersey and at my winter place in Florida, even though I have broadband Internet service in New Jersey but am limited to dial-up Internet access from a different provider in Florida?

Some broadband providers also make available a supplementary dial-up service for their customers, which may be free or cost extra. Check with your broadband service to see if it offers this option.

If not, you could simply use an email account that isn’t necessarily tied to an access provider at all, such as Web-based email services from Yahoo, Google or Microsoft. You could switch to one of these permanently, and use it in both locations, or you can forward your main email address to one of them while you are in Florida. People who send you email wouldn’t have to learn a new address and many Web-based services allow you to set your main address as the “reply-to” address for emails you send.

You can find Mossberg’s Mailbox, and my other columns, online free of charge at the new All Things Digital Web site, http://walt.allthingsd.com.

Write to Walter S. Mossberg at mossberg@wsj.com