While the picture is displayed, the screen capture feature on the recipient's phone is disabled.
Are these services unethical?
Some of you might think that these services are unethical and are only for people with shameful secrets to hide.
But I'm not here to lecture you about your ethics. That's your business, not mine.
I'm here to lecture you about being smart when using email, social networks and other online communications media. Whether you use these services or not, you should know they exist, just in case.
Learn from Petraeus's bad example: Start exercising common sense and avoiding the traps of myopic thinking and "present bias." And start taking advantage of some of the free and easy apps that can keep your secrets secret. With these tools, you can enjoy the benefits of online communication without the risks.
You're a smart person (if you're reading my column, you MUST be smart). So don't do something dumb like Petraeus did. Be smart -- and communicate smart.
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