The Bakeey ZM09 is a new and affordable smartwatch that retails for just US$25.99. However, the smartwatch is IP68 certified, has a large touchscreen and even a temperature sensor.
https://www.notebookcheck.net/ZM09-A-budget-smartwatch-that-is-IP68-certified-and-that-can-measure-body-temperature.533435.0.html