The SENBONO DM20 is a well-equipped smartwatch that includes not only built-in GPS, but also a 4G modem, a large battery and IP67 certification. The device, which has a 1.88-inch touchscreen, comes in two colours and a choice between 1 GB of RAM with 16 GB of storage or 3 GB of RAM and 32 GB of storage.
https://www.notebookcheck.net/DM20-A-well-equipped-smartwatch-with-4G-connectivity-onboard-GPS-a-heart-rate-monitor-and-a-large-battery.478503.0.html