Lilygo has presented its latest smartwatch, the TTGO T-Watch-2020. Highly customisable, the device has a 1.54-inch touch display, Wi-Fi and supports Arduino. The Lilygo TTGO T-Watch-2020 costs less than US$25, too.
https://www.notebookcheck.net/Lilygo-A-customisable-smartwatch-with-touch-Wi-Fi-and-Arduino-support-that-will-set-you-back-less-than-US-25.466013.0.html