Your pain is exhausting enough.
Your app shouldn't be.
Chronic pain sufferers deal with enough. They shouldn't have to fight their tracking app too. Body maps, weather correlations, medication cross-references - none of that helps when you're having a bad day and just need to log a number.
51 million US adults live with chronic pain. 36% of people over 65. And the apps built for them are so bloated that one user said it's "cheaper to just lug around a journal."
Slide your pain level. Tap where it hurts. Add a note if you want. That's the whole app. Because when you're at a 7, you shouldn't need to fill out 50 fields to prove it.