One feature pertains to biometric authentication of a user between devices. In one aspect, an ad hoc personal wireless network may include a primary device and one or more secondary devices using grouping policies such proximity policies and other permissions. The primary device shares a biometric authentication value of a user with the one or more secondary devices. Each secondary device may then perform additional authentication of the same user using a relatively low reliability biometric sensor such as a digital camera for facial recognition, a microphone for voice recognition or an accelerometer for gesture recognition. The secondary authentication results may be combined with the biometric authentication score/level from the primary device to form a final authentication score/level of the secondary device, which is used to authenticate the user of the secondary device for one or more transactions such as consumer purchases, secure content access, or secure control.