This project is a mobile presence system with additional features and improved speed / reliability. I started working on this after having many frustrations with the built in mobile presence system and battery issues with the SmartThings arrival sensor. This project is now compatible with SmartThings and Hubitat.
Each platform has slightly different setup instructions.
https://community.smartthings.com/t/release-improved-mobile-presence-android-only
https://community.hubitat.com/t/release-improved-mobile-presence-android-only