Ask Nigel Parker how many kilometres he ran yesterday, or how he slept last night, or what he ate for breakfast, and he won't just tell you but show you.
There's a histogram measuring his sleep levels over the past month, right down to average bedtime (10.30pm), average time to sleep, (12 minutes and 5 seconds), average wake-up time (6.47am) and even average sleep efficiency (89 per cent).
Also among his smartphone apps are bar graphs measuring average beer intake and a cluster chart of New Zealand mapping his running and walking activity: a big blotch marks the Tongariro Alpine Crossing, which he recently ran. There's a line graph, showing his live heart rate during exercise, which is recorded by an electronic band he wears while out pounding the pavement of Mt Eden.
The Microsoft executive is part of a new generation of motivated self-improvers - everything possibly quantifiable about his personal health, from the pH in his diet to the way he breathes, is crunched in what he calls the "data of you".
For the 38-year-old Auckland father of two, it all began four years ago when he developed the drunk-like symptoms of what he assumed was vertigo.
After seeing his GP and a neurologist, a physiotherapist suggested he undertake regular stretching exercises and break up his day with more periods of activity. From that point on, he made common-sense lifestyle changes - taking the stairs instead of the lift, running longer on his treadmill - but began wearing technology to track his progress.
He eventually blamed his "vertigo" symptoms on a lack of activity, bad diet and too many craft beers, and bought a device to measure every step he walked.
Last year, he redoubled his efforts with a goal to walk 4000km over 12 months and a radical diet change.
Mr Parker purged caffeine, alcohol and acidic processed foods and began measuring the pH in his food, balancing acidic foods with those more alkaline. He ate dinner early, tried to keep 12 hours for evening digestion before a morning meal, read up on sleep research, and lost 10kg in the process.
"My health is now very balanced - in periods of high stress, lack of exercise and overindulgence, I start to regress, but I can read the signs and also get the feedback through data that I need to course-correct," he said.
"My wife thought I was being a bit nuts, and probably a bit self-obsessed, which I think is a fair call - but what's interesting is both my daughters and my wife are now wearing fitness trackers as well."
Along with the many apps and programmes he's been trialling, some from his own company and others like the stress-tracking HeartMath, he uses software to combine the data and find possible correlations.
Reintroducing a moderate amount of alcohol back into his diet, he's even found an app, called Untappd, to gauge his craft beer intake and sample other brews.
Once his diet was back in check, he stopped measuring what he ate.
"I'm convinced that once people have awareness of their own health data and gain predictions and feedback they are more likely to be successful in breaking bad habits and being motivated to improve," he said.
"But I think it's important to not obsess over the process of collecting data - technology should be an enabler and not a distraction."
"It should make us more productive, give us time back rather than take it away. You need a vision of what outcomes you want to achieve and use the technology to help you measure progress."
ProCare clinical director Dr John Cameron said he was aware of a growing trend of data health, which could have its pros and cons.
"You can use that data for a whole range of different things, and really, if you're getting down into that highly granular perspective of your own health, you're probably 99 per cent of the way there anyway."
On the downside, there was the risk of reading too far into anomalies in the data or self-diagnosing - and apps could not replace the GP. "We are trying to take that helicopter view and find out if the patient is heading in the right direction, rather than focusing on those minuscule changes."