[redsymbol]

Doing these two things has worked extremely well for me:

1) Doing deadlifts. This is a strength-training exercise: https://www.youtube.com/watch?v=4AObAU-EcYE

2) Seeing a good chiropractor about twice a month. (You might need to shop around - I can elaborate on how to select a quality one if people want)

You asked about an app. I actually corrected my earlier posture and lower-back problems using the above and not any kind of app to remind myself to get up and move around; the above helped even though I routinely sat 1-2 hours at a time, in a deep coding trance, without moving around. Recently, though, I started using BreakTime (a macOS app) to remind me to look away from the screen, mainly because I believe it's healthier for my eyes. This is a $5 app I've been quite happy with.

All the above is in the anecdotal "works for me" category. Good luck in your effort to find what works best for you!

Edit: The video link above gives a rough sense of the exercise, but the fine details matter greatly, so if you decide to do it I highly recommend studying the relevant chapter of this book: https://www.amazon.com/dp/0982522738/

Edit 2: More about chiropractors: Few are MDs; the ones I've worked with all went through a 4-year, post-bachelors program. In my experience, chiropractors fit on a spectrum, going from ambulance-chasing quacks to gifted, remarkably effective healers. You want the latter. Only way to find out is to pay for about 3 visits; if you and your body are consistently feeling better physically and emotionally by then, you've found a good one. If not, stop, and go find another. So far, the best I've found lean towards alternative medicine (which was really surprising at first... I'm trained as a physicist, and was REALLY skeptical.) Can't say that's a general rule though. Again, all this is my experience; better to get your own experience and evaluate based on that, instead of blindly deciding based on something you read online.

[v64]

Is your chiropractor an MD? I've been skeptical about chiropractors after reading the Wikipedia entry on the practice [1]. As someone with back problems, I've taken chiropractor recommendations from colleagues, and looking into them, they were too alternative medicine for my taste.

[1] https://en.wikipedia.org/wiki/Chiropractic

[dhimes]

At the very least, never let them touch your neck. A friend of mine had a stroke and died after having a neck manipulation. http://chiropracticstroke.com/victims.johnhoffman.php

[v64]

Thanks for sharing this. I was surprised as well to learn that many chiropractors aren't medical doctors.

[jerelunruh]

There seem to be plenty that lean toward non-mainstream practices. However the one I go to was fully planning to have a career as an MD but converted to chiropractic after it helped him with his own health. He tells me that building core muscle strength is the long term solution, not constant adjustments.