After trying several different Pomodoro timers, the one I have settled on and use daily is YAPA 2. I use it on my desktop.

Pomodoro Timer and see here:

Pomodoro Site

I set up a spreadsheet to keep track of the number of Pomodoro rounds I complete each day.

I tried having a timer on my tablet, but there were too many times that I had to put it on a charger, sitting across the room, where I can't see it. Same with my phone. When I get up in the morning to code, I get my coffee, fire up the PC, and put my phone, watch, and earbuds on my charger - all basically inaccessible. So having the timer on the screen for me to see was what I was looking for.

Also, there is a tally with the number of rounds completed, which is super helpful. There have been many times when I use a timer that did not have the tally that a round would be over, and I'd go get coffee or do some stretching exercises, come back and think, "Uh, am I on round three or am I on round four? Which round did I just finish? Argh!" So I searched and had to go through several timers before I found one that had a total count of completed sessions.

The other thing I like about this timer is that you can change its opacity, its size, its color, and you can turn the audio off or on. And then of course you can move the app to different screens or different places on your screen as needed. So this app has helped me move the needle on productivity. It is simple but has a lot of features.