Once a person picks up a comm device, the hyper-sensitive touchscreen automatically reads and records their fingerprint and biometrics. This way, only that person can pick up and use their own comm device. When someone else tries to use it, the system of the device will automatically lock them out. The lock-out protocols stay active for as long as they are touching it. The protocols can be turned off immediately upon the owner of the device touching it.
What's to stop someone else from snapping up another person's comm device?