Ever seen those black and white checkered boxes on Android web sites? They’re QR or “Quick Response” codes, and they can be read from your phone using the Barcode Scanner application from the Android Market. You can scan the codes that are published on web sites and use the results for all kinds of things. QR codes can be encoded with any short piece of text. This application will allow you to browse to a URL, save a contact, or copy the text to use in another application.

Cupcake is the internal Google nickname for the latest version of the Android operating system  (There will be a Doughnut version next). Google engineers stumbled on a great marketing tool similar to Ubuntu’s Hardy Heron, Intrepid Ibex, Jaunty Jackalope scheme. Who doesn’t like dessert?

Unfortunately, Cupcake is quickly becoming known as the update that didn’t show up after the recent announcement and then retraction by T-Mobile. It was officially announced that the random Over the Air (OTA) updates would begin late last week at the rate of about 15% of users each day, but it never came. Reports surfaced that it would be delayed until Monday and then “Early June.”

If you are wondering what version of Android is your phone running and whether it have been updated to the latest version, here is a quick and easy way to check the version on your Android phone: