Timestamp is a small collection of time complications for Android Wear; it includes:

Coordinated Universal Time (UTC), helpful for developers, pilots, and anyone that needs to compare against UTC/GMT/Zulu time. Note that you can achieve similar results with the default Android Wear complications by choosing Reykjavík timezone as a world clock complication. However, if you're bothered by "REY" being on screen at all times, this complication is for you! It also provides a few display features not offered by the world clock complication.

Unix timestamp (available for "large/long" complication slots only), allows you to retrive the current Unix timestamp as milliseconds or seconds since epoch by tapping the complication, the results are displayed on the complication for several seconds.

Timestamp is open source software, available under the Apache 2.0 license. See https://github.com/fardog/Timestamp for more details.