The main theme behind this idea is to develop a self chargable mobile device that works on the phenomenon of piezo electricity.
We know that whenever a stress is being applied on the peizo electric transducer, a certain amount of potential develops across its leads which can be utilized to feed the load.
Using the same principle in this mobile, a peizo electric crystal will be placed beneath the keypad of the mobile and the leads of the crystal connected to the battery being charged.The voltage induced across the crystal leads is proportional to the stress applied on the keypad.
Hence we can have a mobile that does not need external charging; it can be charged instantly by the user as he/she has control over the keypad. So far all the mobiles that are available in the market needs external charging. So with this mobile we can eliminate the problem of external charging. This mobile is especially suited to youngsters who do work on the social networking for chatting as they use the keypad more effectively.
To understand the need of such mobile let us have an example, say you are out of station, you don't have your charger with you and the battery in your mobile is almost discharged and you need to make an urgent call to someone...you cannot be able to do that since you do not have charger with you..this mobile avoids such problems as you can charge it instantly with just a flick on the keypad with your fingertips.