AUSTIN, Texas — Sensors like those used for Apple’s Touch ID, and the heart rate monitor in Samsung’s newer Galaxy devices, have helped change the way users interact with their smartphones, but experts say sensors combined with big data stands to change a lot more — including the entire healthcare industry. During a biometrics-themed panel at SXSW, Dr. Leslie Saxon, who founded the Center for Body Computing at USC in Los Angeles, discussed her vision of a future in which smartphones will enable the collection of biometric data that will be used for everything from individual medical records to predicting the next major disease outbreak.