It’s similar on the surface, but the 24h cake part is the core idea.
The entire day is visualized as a 24-hour circle, so both work and breaks are visible.
Psychologically, that makes it very obvious how the day was actually spent, not just how much time an activity took.
And no, there’s no enforced structure. You’re free to work however you want. You can follow pomodoro or whatever best suits you.
Edit:
If you are interested, check out the screenshots on GitHub readme or give it a try :)