I asked a similar question here, and got a variety of helpful answers.

Best answers include

• Microfiber cloth - with a little (possibly distilled) water
• link to an Apple article on the subject
• Baby wipes

I have found that baby wipes are fine, but your mileage may vary. The microfiber cloth + distilled water sounds like the safest thing to me.

I have tried a few, and the iKlear product is my favorite. The Monster Cable brand iClean is absolutely awful.

http://www.klearscreen.com/iKlear.aspx

-Joe

Eyeglass cleaner! Where I work as an optician , it's sold in bottles for $5 which comes with a microfiber cloth. Different versions can be found at any retail glasses shop and lots of drug stores. We also have pre-moistened disposable lens cleaner towelettes, which you tear open like wet naps and use once then throw away. Not environmentally friendly, but much better to keep in a laptop case, etc, or for travel. They are advertised as working on eyeglasses, but also camera lenses, laptop screens, cellphones, etc. As far as I know theres a VERY little bit of soapy something in them, and a little bit of alcohol.

The best cleaner I have found is Brillianize plastic cleaner ( http://www.brillianize.com/ ) & a microfiber cloth. I have an 8 oz bottle which has lasted me a long time. I also use this, with great results for cleaning & polishing CD's & DVD's. Highly recommended.