I'm a little wary of the usual productivity tools out there.
Don't get me started on those sneaky free ones with built-in ads. Showing ads (a.k.a. distractions) defeats the purpose of using productivity tools. A few ad cents here and there are just not worth it.
The ones with fancy analytics and gamification are also questionable, as the monthly subscription proposals come sooner or later and we are bound to cancel them at some point. Besides, do we really need the graphs, regressions, and virtual coins to be productive? To what degree is the analysis of our procrastination itself a form of procrastination?
For me, the most effective place to start is a minimalist productivity timer done well. Task-independent, free from visual clutter, and customizable to suit different schedules and needs, the timer should provide the foundational units to construct a productive day in the form of work sessions. You are free to choose any additional analytic solutions, but when you use a timer, you could focus and breathe a little.
With all that out of the way, I give you this nice little timer app. No ads, no subscriptions, no distractions.
Best,
Eugene