1. A computer implemented method for determining a user of a computing device, comprising: receiving by a first computing device permission from at least one authorized user of the first computing device to capture sensor data using one or more first sensors of the first computing device for user authentication; capturing first sensor data using the one or more first sensors; determining a set of features from the first sensor data, at least one of the features relating to at least one of a location of the first computing device, an identity of a current user of the first computing device, or an application usage pattern of the current user; generating a score based at least in part by comparing the set of features to a model associated with the at least one authorized user, the score indicative of a likelihood that the set of features corresponds to an unauthorized user; providing the current user with access to at least a portion of functionality of the first computing device based at least in part on the score meeting a first threshold; capturing second sensor data using one or more second sensors of the first computing device for which no permission has been granted for user authentication in response to determining that the score fails to meet a second threshold; determining at least one of the location of the first computing device, the identity of the current user, or the application usage pattern based at least in part on the second sensor data; and sending at least one of the location of the first computing device, the identity of the current user, or the application usage pattern to a second computing device associated with the at least one authorized user.