Estrella Salazar's app Hands with Voice looks to help those with hearing issues. REUTERS / Luis Cortes Estrella Salazar, a 17-year-old science whiz from a working-class town near Mexico City, was ...

Estrella Salazar, a 17-year-old science whiz from a working-class town near Mexico City, was inspired by her sister to develop an app to help deaf and hard-of-hearing Mexicans communicate more easily.