Help us put water-safety expertise in everyone's pocket — offline and free.
Water-safety expertise, normally locked behind labs and public-health departments, directly in your pocket — offline, since the people who need it most often have no signal and no money for a lab test.
PlainWater is an offline-first water-safety app for iOS and Android, built and maintained by EqualInformation, LLC. It helps you find, test, and make water safe to drink, and recognize and treat basic waterborne illness — purification methods and dosing calculators, illness triage and rehydration guidance, emergency sourcing and storage, region-specific risk reference, and disaster-specific checklists, organized across 8 modules and 82 features.
Every feature is designed with privacy at its core — PlainWater's core guidance is 100% on-device, requires no account, and works fully offline. PlainWater is currently in development. A generous free tier covers the life-critical layer for everyone; a one-time purchase or an optional subscription unlocks additional depth. Your support helps us keep building it out, translate it into more languages, and get it in front of the people who need it most.
Every human needs water daily, with no exceptions — but safe water access is not guaranteed across much of the world, and even in developed countries boil-water advisories and disasters are routine. PlainWater matters most exactly when infrastructure and connectivity have already failed, so offline isn't a nice-to-have, it's the whole design.
PlainWater is guidance, not diagnosis or certification. Any visual or camera-based comparison feature is educational reference only, and the app always errs toward "when in doubt, treat or boil it."
Information shared is power shared. Water-safety knowledge should reach everyone, in their own language, for free where it matters most — that is why PlainWater is part of the EqualInformation portfolio, alongside PlainRescue for acute emergencies.
Disclaimer: PlainWater provides water-safety information for educational purposes only and is guidance, not diagnosis or certification. It is not intended to replace a professional water test or professional medical advice, diagnosis, or treatment. If you think you may have a medical emergency, contact your local emergency services immediately.
Tell us what would help, what's unclear, and which features, regions, or languages you'd like to see first. Your feedback directly shapes the product while it's still being built.
Support continued development with monthly or one-time sponsorships directly through GitHub. 100% goes to the developer — no fees.
One-time donation via credit card, Apple Pay, Google Pay, or other payment methods. Secure checkout powered by Stripe.
Your voluntary contribution helps cover development tools, testing devices, app store fees, and ongoing maintenance. Every amount makes a difference.
No features or services are unlocked by a donation — premium features are unlocked only through the app's own one-time in-app purchase. Donations are entirely voluntary and do not create any obligation, entitlement, or guarantee of specific features or outcomes.