I saw your recent review of ICE, the emergency medical information app for the iPhone. But my iPhone is set up to require a passcode to get to the home screen and run apps. Is there any way to display emergency contacts before a person enters the passcode?

There are some apps that allow you to customize the wallpaper of your iPhone or iPod Touch by adding a few lines of text that can be seen before it’s unlocked. One, called Close Call, displays a red cross and, next to it, an emergency phone number, and one brief line about, say, a key allergy or medical condition. The app is free, and is from a company called Polka, at polka.com.

I installed VMware Fusion on my Mac so I can run a virtual Windows XP computer on the Mac. When in the virtual Windows environment, I use security software. If I have the Fusion program shut down completely when I am not using it, will my computer be vulnerable to Windows security threats?

The vast majority of viruses, spyware and other malicious software is designed to run on Windows and cannot run natively on the Mac’s built-in operating system. So, while you are wise to use security software in your virtual Windows PC, any malware it misses won’t be able to run when Fusion is shut down. While even a virtual PC can get real viruses, this faux PC just disappears when Fusion is shut down, and so does all its software, including viruses.

But simply because Windows-based malware can’t run on the Mac’s OS, that doesn’t mean you don’t have to be careful. You can still be tricked by false email and Web sites into giving up personal information.

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