Here is a smart alarm you can use in your dorm room, hotel or anywhere else to stop intrusions. The Streetwise Volumetric Alarm is smart enough to sound an alarm before intruders enter. It can be used to monitor windows and doors. The device has a protection range of 1000 ft2.
This tiny alarm has 3 settings. It measures only 4.5″ x 1.75″ x 6.625″.