1. A method for authenticating a user of an electronic device that includes a biometric sensing device, the method comprising: capturing, at a first time, as part of background operations of the electronic device, a first biometric image as the user interacts with the electronic device; receiving first user identification data (UID) from the user as the user interacts with the electronic device; tagging the first biometric image with the first UID when the first biometric image and the first UID are received within a given time period of each other; if the first biometric image and the first UID are received within the given time period of each other, assigning the tagged first biometric image to a cluster, wherein the cluster comprises one or more biometric images associated with a respective biometric attribute of the user; if the first biometric image and the first UID are not received within the given time period of each other, assigning the untagged first biometric image to the cluster; capturing, at a second time, as part of the background operations of the electronic device, a second biometric image as the user interacts with the electronic device; determining if the second biometric image matches the first biometric image in the cluster; and providing the user with automatic access to the electronic device or to the application on the electronic device only when the second biometric image matches the first biometric image and the first biometric image is tagged with the first UID.