Clock.app is a simple, accurate, ad-free digital clock.
It's a digital clock, does what it says on the tin, etc. That said, it does have some basic features:
Any changes you make will change the URL in the address of Clock.app, so you can bookmark or copy or share the clock with your preferred options.
The h= value in the URL address is the hue (the color) of the clock. You can set it to any value between 0 and 360 to get different colors by just changing the value in the URL. Whatever value you pick will be added to the default set for that session. For example:
For devices which support Dark Mode, the clock will invert to a darker, dimmer style based on the hue input.
Clock.app gets the time from the server it runs on, rather than the device you are using. Your desktop or phone time can be off by a little or a lot for various reasons. The server that Clock.app runs on synchronizes its clock using the Network Time Protocol (NTP). So if you open Clock.app on several devices, you should see that all the clocks are in sync to within a few milliseconds.
Still, it won't be perfectly accurate because of various things like light travel time between you and the Clock.app server, thermal fluctuations in your devices, spacetime curvature anomalies, etc.
Clock.app makes us of the Luxon JavaScript time library in order to display the correct time for your timezone and pick the right locale in choosing whether to show time in 24 hour format.
There are no ads on Clock.app and it is free to use.
Send feedback and bug reports to feedback@clock.app