I won't hide it, I'm totally all over this app.
I would give it an Apple Design Award. It feels well thought out, well executed, light and all the functionalities you should need to track your working hours.
About ten years ago, I put together an AppleScript app with a similar goal. Then I tried some automated time tracking apps, iPhone based time tracking apps, Google Sheets, GitLab time tracking with Pomodoro timers and now finally Tyme. It's the perfect solution for me to track both my billable and non-billable hours, keep the clients happy and up to date on my progress, improve my estimations and review my days/weeks/months productivity. I can even do Pomodoro sessions with it(even if it's clearly not part of the apps goals).
The interface is simple and attractive and behind the simplicity you'll find all those little settings to keep you happy on the long run.
Loving it and thankful for it!