Here is a pet environment sensor that sends you safety alerts to your iOS/Android device. The Pet Monitor 4G Lite Environment Sensor comes with 4G Verizon service. It has a peel & stick design, so you can put it inside your car/RV easily. You can configure up to 5 emails and mobile numbers to get safety alerts.
The device doesn’t require WiFi to work. The battery lasts up to 2 hours on battery.