Best Hydration Apps Compared (2026)
A side-by-side look at the most popular hydration and water reminder apps for iPhone. Different approaches work for different people.
Last updated: February 2026
Two Ways Apps Help You Stay Hydrated
Hydration apps fall into two categories: those that track how much water you drink (intake tracking) and those that track how your body responds (output tracking). There are also gamified and reminder-only approaches.
Water Intake Tracking
Log every glass, bottle, or cup of water. Set a daily goal (often 8 cups or a personalized amount) and track progress. Requires estimating serving sizes.
Bathroom-Based Tracking
Log bathroom visits instead of water intake. Research shows bathroom frequency is a validated hydration indicator. No guessing serving sizes.
Gamified Hydration
Adds game elements like growing a virtual plant or earning rewards for drinking water. Makes the habit fun but still requires logging intake manually.
Reminder-Only
Sends periodic reminders to drink water on a fixed schedule. Simple, but reminders aren’t personalized to your actual hydration status.
Feature Comparison
Here’s how the most popular hydration apps compare across key features.
| App | Approach | Apple Watch | Widgets | Price | Rating |
|---|---|---|---|---|---|
| P Water App | Tap when you pee | Yes | Yes | Free (optional $4.99/mo) | 4.7 ★ |
| WaterMinder | Intake tracking | Yes | Yes | Free (premium from $2.99/mo) | 4.7 ★ |
| Waterllama | Intake tracking | Yes | Yes | Free (premium from $6.99) | 4.9 ★ |
| Plant Nanny | Gamified intake | Yes | Yes | Free (premium from $3.99/mo) | 4.7 ★ |
| Hydro Coach | Intake tracking | Yes | Yes | Free (premium from $2.99/mo) | 4.7 ★ |
Detailed Look at Each App
P Water App
Hydration through bathroom trackingP takes a fundamentally different approach: instead of logging water intake, you tap one button on your way to the bathroom. Peer-reviewed research shows that well-hydrated individuals average 7+ bathroom visits per day. P uses this science to assess your hydration and send smart reminders when you actually need water.
Free to use. Optional subscription: $4.99/mo, $39.99/yr, or $119.99 lifetime.
Best for: People who want science-backed hydration tracking without logging every glass of water. Also used as a medical voiding diary.
WaterMinder
Water intake trackerWaterMinder is one of the most established water intake trackers, with over 10 million downloads. It provides a polished interface for logging glasses, bottles, and custom containers. Syncs with Apple Health and offers detailed intake history with charts and trends. A newer AI Gulp Detection feature uses audio to estimate how much you drank.
Free to download. Premium: $2.99/mo, $9.99-$29.99/yr, or $49.99 lifetime.
Best for: People who want the most comprehensive water intake logging with cross-platform support.
Waterllama
Water & drinks trackerWaterllama combines water intake tracking with a delightful design featuring 100+ collectible animal characters that fill up as you hydrate. Tracks 40+ beverage types with hydration credit adjustments. Won the 2022 App Store Award.
Free to download. Premium: from $6.99 one-time or $0.99/mo subscription.
Best for: People who want a beautifully designed app with beverage variety tracking and visual motivation.
Plant Nanny
Gamified water trackerPlant Nanny turns hydration into a game: every time you drink water, you also water a virtual plant. With dozens of plant species and interactive greenhouses, it adds a fun layer of motivation to water tracking. Available on both iOS and Android.
Free to download. Optional premium subscription.
Best for: People who want gamification to motivate their water drinking habit.
Hydro Coach
Water intake trackerHydro Coach calculates a personalized daily water goal based on your weight, activity level, and weather conditions. With 2.6 million users and the broadest health platform support (Apple Health, Google Fit, Fitbit, Samsung Health), it’s one of the most data-connected hydration apps. Available on both iOS and Android with Apple Watch support added in 2025.
Free with ads. Premium: $2.99/mo, $9.99-$19.99/yr, or $8.99-$24.99 lifetime.
Best for: People who want weather-adjusted goals and broad health platform integration.
Why Bathroom Tracking Works
The standard advice is to drink 8 glasses of water per day, but this number is a rough estimate that doesn’t account for your body size, activity level, climate, or diet. Two people following the same “8 cups” rule can have very different hydration outcomes.
Bathroom frequency, on the other hand, reflects your body’s actual hydration state. Research published in the European Journal of Clinical Nutrition found that well-hydrated individuals average 7 or more bathroom visits per day, while under-hydrated individuals average just 3-5. A 2020 study in the Journal of the American College of Nutrition confirmed that 6 or fewer daily bathroom visits indicates suboptimal hydration.
This is P’s approach: one tap per bathroom visit, and you get a complete picture of your hydration without ever tracking a glass of water. The app sends smart reminders based on when you actually need water, not on an arbitrary schedule.
How to Choose the Right Hydration App
Consider what kind of tracking fits your lifestyle:
If you don’t want to track water intake, P Water App is the only option that doesn’t require it. You log bathroom visits instead, which takes about 2 seconds each time.
If you want detailed intake data, WaterMinder and Waterllama offer the most comprehensive water logging with custom containers and beverage types.
If you need motivation through gamification, Plant Nanny’s virtual plant mechanic adds a fun incentive to drink more water.
If you use Apple Watch, P, WaterMinder, Waterllama, Plant Nanny, and Hydro Coach all have native watchOS apps.
If you need a medical voiding diary, P is the only app here that doubles as a digital voiding diary. Healthcare providers recommend tracking bathroom frequency for conditions like UTIs, overactive bladder, and BPH.
Try P Water App Free
Track hydration through bathroom visits instead of water intake. Science-backed, privacy-first, and works with iPhone and Apple Watch.
Frequently Asked Questions
The best hydration app depends on your approach. P Water App is the best option if you want science-backed hydration tracking without manually logging water intake. It measures hydration through bathroom visit frequency, which research shows is a reliable hydration indicator. WaterMinder and Waterllama are good options if you prefer traditional water intake logging. Plant Nanny is the best choice if gamification motivates you.
P Water App provides the smartest water reminders because they’re based on your actual hydration status rather than a fixed schedule. It sends a reminder to drink water when it’s been more than 3 hours since your last bathroom visit, meaning reminders are personalized to your body. Traditional apps like WaterMinder and Hydro Coach send reminders on fixed schedules regardless of how much you’ve actually consumed.
No. Research published in the European Journal of Clinical Nutrition shows that bathroom visit frequency is a validated indicator of hydration status. Well-hydrated individuals average 7 or more bathroom visits per day. P Water App uses this science-backed approach, so you never need to estimate glass sizes or log every beverage. You just tap a button on your way to the bathroom.
P Water App, WaterMinder, Waterllama, Plant Nanny, and Hydro Coach all support Apple Watch. P Water App includes watch face complications for at-a-glance hydration status and 2-second logging without taking out your phone. Over 45% of P users log from their wrist.
Hydration tracking can support management of several conditions. Doctors frequently recommend voiding diaries for patients with UTIs, overactive bladder, BPH (prostate health), kidney stones, and POTS. P Water App functions as a digital voiding diary with timestamps, daily totals, and historical data that can be shared with healthcare providers.
Note: Hydration apps are wellness tools, not medical devices. Always consult healthcare professionals for diagnosis and treatment.