NailO is an inconspicuous wireless track pad that is so small it can fit on your thumbnail. It looks a bit like decorative nail paint and the hope is that in the future the individual will be able to top it with an exchangeable nail art that best represents their individuality. There is also thought being given to be able to color coordinate the appearance to what one is wearing. The unit is light weight and currently functions at 92% accuracy. It would allow you to be able to swipe info while both hands are busy. You would be able to answer the phone while cooking or follow a recipe without needing to stop what you are doing. It could also be used to help you follow instructions while doing work like soldering.
Other uses would be if you needed to communicate unnoticed while in a meeting. It functions with the same kind of touching as an iPhone touch screen. When used on the thumb the other fingers can access it and it will not interfere with what are you doing or holding. It allows you to tap your thumb with your index finger to send a wireless message by way of Bluetooth to a mobile unit or PC. Work is being done to design a battery that would be only one half of a millimeter thick. Because of its size it would need to be energy efficient so deactivated when not in use. To prevent accidental nail calls made by misinterpreted gestures there is a proposed two second activation press that would trigger it. You would be able to program a certain gesture in to respond a certain way. For example, swiping your thumbnail would call home.
NailO is a wearable technology that is in the designing stage and probably will not be available for at least three years. It will be ideal for subtle interaction where voice or big motions are not appropriate. It would allow your nail to be part of a track pad and would become part of the computer. You can take it off, it will not be a permanent part of you, so you are still in control of it.