Meditate is a nice and simple stopwatch for meditation. It automatically logs all sessions. You can create complex presets and easily access sessions.

I used Meditation which has a beautiful and clean ui for a long time in addition with Table Habit tracker to log the sessions. I liked the setup and if you only need a stopwatch, go for it. I had to use two apps and log manually. It was annoying to switch between timers and you couldn't select custom durations easily, or even at all.