Mobile phones are widely recognized as a potentially transformative technology platform for developing nations. However, for designers and programmers in the developed world to create viable applications for mobile phones involves first identifying and communicating user requirements for diverse users. We define diverse users as those from a substantively different cultural context than that in which the technology design occurs, including developing regions. This paper presents a case study outlining our process of using data from prior research to (1) identify a tenable mobile phone product concept for mobile phone users in Kyrgyzstan; (2) detect and communicate user requirements for that product concept to a design team; and (3) develop a working prototype of the concept for usability testing. Our resulting concept meets important user needs and goals for mobile phone users in Kyrgyzstan. We believe the process by which we developed and discuss these user requirements and the subsequent prototype can serve as an example to others concerned with creating user-centered products and services for diverse users including those in developing countries.