A mobile wireless communications device may include a portable housing, a wireless transceiver carried by the portable housing, an input device carried by the portable housing, a display carried by the portable housing, and a processor carried by the portable housing and coupled to the wireless transceiver, the input device, and the display. The processor may perform a time alarm function having a time alarm value settable via the input device, and generate an alarm indication upon reaching the time alarm value. The processor also may generate a first time alarm function GUI on the display including a first selectable menu list for the time alarm function, and generate a second time alarm function GUI including a second selectable menu list on the display different from the first selectable menu list when a current time is within a threshold time of the time alarm value.