Criteria and Constraints

The solution is going to need to be small so it is convenient for users to use. The cost will have to be low so it won't take a lot of money to make. Also, it should be quiet so it can charge your phone without bothering the user. Some other constraints are it will have to be able to be done in time for presentation and will have to be made out out of materials on hand. Finally, it needs to be efficient and not waste a bunch of electricity.