If you're in the flow, do you take the break anyway or skip it? 

I skip it (because in the flow I don't want to be interrupted by a break) and start immediately the next pomodoro with longer interval.

If you skip it, it might be best to save the break up for later, so you get a longer break after longer work (somewhat like Third Time). As the academic research suggests, not surprisingly, that people need longer breaks after working longer.

Yes, sounds reasonable, I will probably make the breaks proportional to pomodoro length.

(1/3 feels like a bit too much though, e.g. 8 minute break for each 25 minute pomodoro. 1/5 to 1/4 would be closer to classic 25-5)

I think making pomodoros longer when you're in flow makes sense, as does making them shorter if you're distracted because your attention span is short today. Though being distracted or interrupted by something external outside your control doesn't seem a reason to shorten the next pomodoro.

Yes, in fact it's not automatic shortening/extending of the interval in my app, I just have convenient shortcuts for "start pomodoro 5 min longer / 5 min shorter / the same length", so I sometimes decide to keep current interval, too.

Interesting approach, thank you.

A while ago I addressed the same concerns by inventing adaptive variation of Pomodoro, where the interval length is fluctuating all the time:

• start with 25 minutes pomodoros
• in case I feel that I'm in the flow and don't want to stop for a break, I immediately start a new pomodoro with length +5 minutes longer than previous
• in case I get distracted/interrupted before finishing a pomodoro, I start the next pomodoro with length 5 minutes shorter than previous.

I use my own app to implement it: https://github.com/gumb0/adaptive-pomodoro
(perhaps I could adapt it to try out your approach)

For me they still don't work.

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