In addition to the numerous things your cell phone now doubles as, it could soon act as a sort of pen. Through a sophisticated computer algorithm using a cell phone's embedded accelerometer, the device could interpret your 'air writing' and record the letters. While a program is expected to be released within a few months, I think this will remain more of a novelty depending on your type of phone. I do not think I am alone in saying that I can type much faster then I can write. The strong likelihood is that typing on my QWERTY keyboard on my phone will be much quicker then trying to 'air write'. If you have a phone withing a full keyboard, one that requires multiple key strikes for each letter, 'air writing' may be faster.
""By holding the phone like a pen, you can write short messages or draw simple diagrams in the air," said Sandip Agrawal, an electrical and computer engineering student at Duke University in North Carolina.
The air-writing app takes advantage of accelerometers already inside cell phones such as Apple's iPhone. Accelerometers normally keep track of phone movements and orientation, such as having the display screen rotate from portrait to landscape mode."