A method comprising: determining, while in a high-level state of a user equipment during which a user is interacting or has recently interacted with the user equipment, a movement of the user equipment, the movement indicating that the user equipment is being or has been moved, the determining based on inertial data received through an inertial measurement unit integral with the user equipment; determining an intent to disengage based on radar data indicating that the user is retracting an arm or hand away from the user equipment, looking away from the user equipment, turning the user's body away from the user equipment, or walking away from the user equipment; and responsive to the determination of both the movement and the intent to disengage, reducing the high-level state of the user equipment from the high-level state to an intermediate-level state or low-level state, the high-level state being a high-access, high-power, or high-information state, the intermediate-level state being, respectively, an intermediate-access, an intermediate-power, or an intermediate-information state, and the low-level state being, respectively, a low-access, a low-power, or a low-information state and the high-level state is the high-access state, the high-access state being an unlocked state in which the user is authenticated by the user equipment; and reducing the high-level state reduces the high-access state to the intermediate-access state or the low-access state, the intermediate-access state permitting less access than the high-access state to data, applications, functions, components, or accounts of the user equipment and the low-access state permitting less access to the data, applications, functions, components, or accounts of the user equipment than the intermediate-access state, the low-level state being a locked state in which the user is not authenticated by the user equipment and the method further comprising: determining, based on the radar data or later-received radar data, an intent to engage by, or a presence of, an unauthenticated person, the unauthenticated person being a non-user, and, responsive to the determination of the intent to engage by, or the presence of, the non-user, ceasing to maintain the high-access state; and returning to the high-access state responsive to determining that the non-user is no longer present. determining, while in a high-level state of a user equipment during which a user is interacting or has recently interacted with the user equipment, a movement of the user equipment, the movement indicating that the user equipment is being or has been moved, the determining based on inertial data received through an inertial measurement unit integral with the user equipment; determining an intent to disengage based on radar data indicating that the user is retracting an arm or hand away from the user equipment, looking away from the user equipment, turning the user's body away from the user equipment, or walking away from the user equipment; and responsive to the determination of both the movement and the intent to disengage, reducing the high-level state of the user equipment from the high-level state to an intermediate-level state or low-level state, the high-level state being a high-access, high-power, or high-information state, the intermediate-level state being, respectively, an intermediate-access, an intermediate-power, or an intermediate-information state, and the low-level state being, respectively, a low-access, a low-power, or a low-information state and the high-level state is the high-access state, the high-access state being an unlocked state in which the user is authenticated by the user equipment; and reducing the high-level state reduces the high-access state to the intermediate-access state or the low-access state, the intermediate-access state permitting less access than the high-access state to data, applications, functions, components, or accounts of the user equipment and the low-access state permitting less access to the data, applications, functions, components, or accounts of the user equipment than the intermediate-access state, the low-level state being a locked state in which the user is not authenticated by the user equipment and the method further comprising: determining, based on the radar data or later-received radar data, an intent to engage by, or a presence of, an unauthenticated person, the unauthenticated person being a non-user, and, responsive to the determination of the intent to engage by, or the presence of, the non-user, ceasing to maintain the high-access state; and returning to the high-access state responsive to determining that the non-user is no longer present. determining, based on the radar data or later-received radar data, an intent to engage by, or a presence of, an unauthenticated person, the unauthenticated person being a non-user, and, responsive to the determination of the intent to engage by, or the presence of, the non-user, ceasing to maintain the high-access state; and returning to the high-access state responsive to determining that the non-user is no longer present.