Disclosed herein is a small form factor device comprising: a power source, a force sensor, a wireless communications module, and a processor. The processor is configured to implement a proximity monitoring process involving periodically operating the wireless communications module to transmit advertisements. The processor is also configured to determine whether device stationary criteria are satisfied based on force signals received from the force sensor and, if the device stationary criteria are satisfied: cause the wireless communications module to transmit a device stationary message; and cause the small form factor device to enter a power saving mode in which the proximity monitoring process is suspended.