Udell is a well-known Android developer, mostly thanks to Wearable Widgets. If you're getting ready for Google I/O 2018, or you're just looking for a fun Android Wear Wear OS watch face, Udell's new 'I/O 2018 Watch Face' is pretty great.
The design matches the Google I/O 2018 countdown timer, with fully-animated numbers. The whole thing looks great, plus it's completely free and open-source. You can download it from the Play Store below.