I need to find a company which can configure mobile phones?

My business idea involves a new use for existing technology but need help in finding a company which will build what is essentially a modified mobile phone and allow me to retain design rights on the use. An idea so simple I genuinely can't believe that it hasn't been done (and the need for it in my own business is what is driving the idea). I have capital and time but technology based business is outside my competence zone. All assistance greatly appreciated.