I've eschewed time-clocking tools and apps for most years of freelancing because I didn't want to feel like I was clocking in and out of a factory or an office. (One of my temp jobs before university was working as a clerk in an electronics factory and we had to punch in and out on time cards, same as all the other non-office employees.) What made me change my mind now was realising that after freelancing for more than six years, I often have only a very vague idea of how much time I've put in on each assignment because I'm often juggling multiple projects at the same time. This way, at least I can tell people with some confidence exactly how much time the work takes out of me (and believe me, it's surprising sometimes).
As for Pomodoro, call it a last-ditch attempt to kill the procrastination monster that's plagued me for most of my life. (My flatmate in London can attest to that; her favourite line is, "I always thought she was this super-organised person, and after living with her, I found out she's always doing things at the last minute!") Pomodoro teases me with the reward of a five-minute break after every 25 minutes of solid work, which is great even if use those five minutes just to do the dishes or refill the water jug. More importantly, it helps to break up extended tasks (like long pieces of writing or editing) into more manageable portions, so I don't feel I'm spending all afternoon at it.
Even though I am. It's just a trick, I know.
Tick tock, tick tock, time for bed.