Released as an open source project at github.com/NosillaCast/time-shifter-clock
The purpose of this clock is to help you find and communicate a time in the future across multiple timezones when planning a meetup.
They will see the date/time exactly as you've sent it. If they don't like the time chosen, they can shift time themselves and send it back to you as an alternate proposal.
If you find Time Shifter Clock useful, add it to your mobile device's home screen and you'll get a progressive web app with a pretty icon and no URL bar.