Electronic data transfer between trust contacts

Mobile devices can be wirelessly linked to an increasing number of wearable devices. Sensors included in both mobile and wearable devices possessed by a first party and a second party can detect physical, biometric, or environmental inputs. A logic circuit in each of the portable electronic devices can autonomously determine whether these inputs are indicative of a trusted contact between the first and the second parties in various social, business, and commercial settings based at least in part on local social, business, and interpersonal practices and norms. A first portable electronic device possessed by a first party and a second portable electronic device possessed by a second party may autonomously exchange public or private information based on detecting a trusted contact between the first party and the second party. Such devices may also track ongoing trusted contact between the first party and the second party in social, business, and commercial settings.