Portable door vibration sensor in white with "lever lock suction cup" so you don't need water. Looks of a round room temperature sensor. No visible branding and made in white, it is made for the safety of individuals and must be inconspicuous. Connects to hotel wifi and can send immediate e-mails when triggered to one or several e-mail addresses. 2026-09-04: Reverted from mobile app notification: mobile app requires development, approval and maintenance e-mail lower cost than text messages Hard sensitivity setting, which cannot be set with stolen mobile. Needs wifi login, which can have guest access form, without keyboard. Wifi login sent from mobile to device using bluetooth or bluetooth connection to login on wifi. Apples AppleTV solution for wifi login? Wifi so you don't have to leave your phone in the hotel room when away.