In this resource guide I list the most popular smart home sensors.
Be aware that most of these Samsung SmartThings sensors require a Samsung SmartThings Hub or alternative to work.
Most of their sensors also work with Google, Amazon Alexa, SmartThings, and Zigbee communication protocols. Be sure to read the specs for each device.
Samsung GP-U999SJVLCAA Smart Things Water Leak Sensor - Automate Lights & Siren For Alert – ZigBee | Accessory to Smart Things Hub White - I have a water heater on the second floor. So immediately catching water leaks is one of my highest priorities for home automation.
Samsung SmartThings Multipurpose Sensor [GP-U999SJVLAAA] Door & Window Sensor - Zigbee - White - doors, windows, cabinets, refrigerators, etc. You can put these simple sensors on anything where you need to detect open and close events. All-in-one open/close, vibration, orientation, angle (tilt), and temperature sensor for multipurpose functionality