I have an IFTTT mobile button that I can click everytime I masturbate, one button for masturbating to straight porn/fantasies, one for non-straight. The click makes an entry in a spreadsheet recording date and time. This then adds on to graphs showing straight vs. gay shags, average sessions per day, per week, on particular days of the week, time of day, and number of hours between sessions. Until now I had not been logging sexual intercourse, though I can probably make provisions for that too. Have been doing this about 4 months now. Also, I do not note the length of sessions since that's inconvenient, subjective, and not as useful in my opinion.
I'd like to say that it's been great doing this, since I have a better idea of my habits, and now masturbate 60-65% fewer number of times per week or month than I used to with greater control over temptations. I also go through less porn than earlier, last longer (and can enjoy them in full), edge 2-4 times every time, and have a higher quality bar. Unsurprisingly, my ejaculations during masturbation have become more pleasurable, and my sexual performance has improved too. My last hookup also commented on the strength and quantity of my ejaculate.
It's very convenient, and it seemed weird to me at first, but now I'd recommend it to everyone for the above reasons.