I'm not exactly a neat freak -- one look at my office would confirm that -- but I do find smudges on my phone screen to be annoying. I'm always wiping it clean with a soft cloth.
Turns out that I have likely been adding a level of security to my phone without ever realizing it.
An article on CNET suggested finger smudges on touchscreen smartphones can reveal passwords.
Researchers at the University of Pennsylvania found that oily residue on the fingers leaves a trail when entering the graphical password systems on the Google Nexus One and HTC 1, and the residue isn't very easy to remove. According to the researchers' report:
We believe smudge attacks are a threat for three reasons. First, smudges are surprisingly persistent in time. Second, it is surprisingly difficult to incidentally obscure or delete smudges through wiping or pocketing the device. Third and finally, collecting and analyzing oily residue smudges can be done with readily-available equipment such as a camera and a computer.
Touchpad keyboard password entry aren't as much of a security risk since the keyboard is used for many different functions, not just passwords.
As I see it, the concern here is if the phone is lost or stolen, there is a very good chance of the password code being broken and then whatever information is available on that smartphone is at risk. All the more reason to keep those soft cloths and electronic-device cleaners handy.