I am a Palm Treo user and would like to get an iPhone for the apps. But I have tried the virtual keyboard on the iPhone in the store and hate it. Is there a stylus you can use for better accuracy, or some software trick?

I don’t know if they improve accuracy, but there are several stylus brands made for the iPhone and iPod Touch. They are aimed at making typing easier, especially if you have long nails or are wearing gloves. One example is the Pogo, a $15 iPhone stylus from a company called Ten One Design, at tenonedesign.com.

In addition, there are several iPhone apps that attempt to help typing accuracy by allowing you to compose emails, text messages and Twitter posts using a wide, landscape keyboard rather than the narrower standard keyboard. You type your message in these apps, and then the app sends them to the iPhone’s email program for transmission. One that I have used is called TouchType. It works with email and Twitter, and costs 99 cents.

Another interesting solution is a free app called ShapeWriter, which lets you type by sliding your finger along a keyboard to connect the letters in words. You never have to lift your finger until you are done with a whole word. Messages you compose in ShapeWriter can be saved as notes or shipped to the email program for sending.

Finally, I should note two things about typing on an iPhone. First, it’s difficult to know if you’ll be comfortable with it from just a few minutes in a store, because it usually takes a few days to master. Second, some people won’t ever find it acceptable, and these folks should choose a phone that has a physical keyboard.

In your review of the new version of the Safari Web browser, you said some Web sites were publishing methods for undoing some of the changes in it that you criticized. Can you explain how I can do that?

There are two methods for changing Safari 4 so it looks and works more like the previous versions, while retaining its faster speed. One method involves typing techie commands into the computer. But, for mainstream users, I recommend another: downloading a new free utility called Safari 4 Buddy. It’s available at swoon.net/site/software.html.

Safari 4 Buddy allows you to just check off buttons that can change the placement of tabs in Safari 4 so they’re under the toolbars, rather than at the top of the screen, and restore the blue page-loading progress bar that Apple killed. It also permits users to change other settings Apple omitted from the browser’s Preferences menus. I have tested it and it works.

However, this utility works only on the Mac version of Safari 4. I don’t know of any way to make these changes in the Windows version. Also, there’s no guarantee that Apple won’t make future modifications to the browser that might reverse any customizations Safari 4 Buddy makes.

• 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 bought an iPhone and was frustrated that my fingers appear to be too large to type properly on its virtual keyboard. Is there a stylus that works with the iPhone?

I hadn’t realized this until recently, when a friend who bought one showed it to me, but, yes, there is. The iPhone wasn’t designed to operate with a stylus, and the small, thin, hard kind that one uses with, say, a Treo, doesn’t work right with the iPhone. But there are some companies that sell a wider type of stylus with a soft tip that approximates a small fingertip, and is designed for the iPhone.

If you type “iPhone stylus” into a search engine, or an online store like Amazon.com, you will see a number of inexpensive choices. One downside: the iPhone doesn’t have a built-in slot for a stylus. My friend carries his, which has a clip on the end, like a pen, in his pocket.

I just purchased an external hard drive for my PC that connects through a USB port to back up photos and important files in the event of a computer crash. Would this hard drive be affected if my main hard drive crashed? Should I disconnect the external drive when it’s not in use?

The two hard disks are separate devices, and if one has a mechanical failure, it doesn’t affect the other. There might be some scenarios in which a problem with the computer itself, as opposed to a breakdown of its internal hard disk, could affect the external drive. And malicious software could corrupt or erase files on the external drive. An electrical surge could also affect both drives, or fry the computer itself.

Many people can’t disconnect their external drives, because they use automated backup programs, or frequently save files to the drives. If you are doing only occasional manual backups, you could disconnect the extra drive when not in use, so you’d feel more comfortable. But, for maximum peace of mind in case of an electrical surge, you should disconnect it not only from the PC, but from the electrical outlet as well, even if you are using a surge protector.

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

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