A goal with arithmetic behind it
30–45 ml per kilogram, depending on how active you are. Hydra+ adds a weather adjustment above 25°C. You can always set your own number instead.
Android · Daily water tracker
Drink deep.Live light.
A premium water tracker for Android. Hydra sets a goal that fits your body, fills the ring with one tap, and grows a garden out of the days you keep.
1K+
Google Play downloads
4.9★
rating · 25 reviews
0
accounts to create
76% of goal
5-day streak
2,220 ml today
04 m · The ring
Eight glasses is a slogan. Your goal is a calculation.
Your weight and activity set the base. Hydra+ can raise it on a hot day. Coffee counts for what it is. The ring tells you the truth, not a rounded-up version of it.
Every drink, honestly credited
Water counts 1.0. Coffee and tea count 0.7. Juice counts 0.9. Log a coffee and the ring moves by what it actually hydrates.
One tap, then out of the way
Four quick pours, a custom amount, undo, notification actions and a home-screen widget. Logging should take a second, not a screen.
What counts250 ml water
250
ml counted
250 ml of water counts as 250 ml. The baseline for everything else.
09 m · The record
The week, the month, the hour it all happens.
Bars for the week. A calendar for the month. A hydration score, your drink mix, and the hours you actually drink. The record is there when you want it, and out of the way when you don't.
19.1L
This week
79/100
Hydration score
32.8L
Tracked all time
Sample data, as shown in the app.
Weekly and monthly charts
See the shape of the week, the goal-hit rate, your daily average and the drink you reach for most.
Deeper insights in Hydra+
The month calendar, hour heat map, drink mix, consistency, trends and predictions are premium. The weekly view is always free.
Streaks that don't punish you
Bank a Streak Freeze every seven goal days, up to three. Miss a day and one covers it automatically. A lost streak can always be restored, free.
Yours to take with you
Hydra+ exports every log as CSV and your insights as a PDF report. No lock-in, no account, no request to a server.
14 m · The garden
A garden that grows out of the days you keep.
Every sip nudges your companion forward. Six species, five living weathers, and a journal of visitors — from the first ladybug to a phoenix. It is the least utilitarian part of Hydra, and the reason people come back.
Oak
Always yours
Cherry Blossom
7-day streak · Level 5
Bamboo Grove
14-day streak · Level 10
Bonsai Pine
30-day streak · Level 20
Saguaro Cactus
50-day streak · Level 30, or Hydra+
Sacred Lotus
60-day streak · Level 40
Weather you can see
Clear, sunny, rain, snow and fog are drawn into the scene — not just printed in a forecast. Your goal moves with the temperature when adaptive weather is on.
Fourteen visitors
Ladybug, firefly, hummingbird, frog, phoenix, kitsune, unicorn and more. The creature journal fills as your garden reaches new stages and conditions.
Yours to keep
Save the garden as an image or send it to someone. Growth persists across sessions, devices and your Drive backup.
Marginalia · what you won't find
01
An account.
There is nothing to sign up for. Open the app and log a glass.
02
A streak for sale.
Freezes are earned at seven goal days. They are never a purchase.
03
A chatbot in the reminders.
Plain, encouraging copy on the interval you chose. No guilt, no generated nudge.
04
A Hydra server.
Your log lives in a database on your phone. Analytics and crashes go to Firebase; backups are yours. There is no Hydra server to send anything to.
19 m · The quiet
The reminder that knows when to stop.
A hydration app should not become another thing shouting at you. Hydra reminds you on the interval you chose, then backs off when you do. No streak shaming, no “you're falling behind.”
Eight a day, at most
A hard ceiling, no matter how long your waking window is. The default interval is sixty minutes; you choose the rhythm.
Swipe, and the gap widens
Dismiss a reminder and the next one waits twice as long, then four times. If you're busy, Hydra takes the hint.
Pause for two hours
One action on the notification, next to snooze. Back off without turning reminders off — and quiet hours follow your wake and sleep times.
Quick add from the tray
Log 250 or 500 ml without opening the app. The widget does the same from the home screen.
Plain copy only. The quirky and AI-written nudge pipelines were removed in 1.20.2.
30 m · The logbook
Every release, on the record.
Small releases, often. What changed, when, and why — written down in the same voice as the app. The current edition is 1.20.5.
- A refined garden: a smaller, warmer sun with a softer glow, mountain ridgelines with a subtle sunlit edge, and fuller, less perfectly round canopies.
- Every rewarded ad pays out: finishing the level-up ad banks a Streak Freeze for free users — and both rewarded ads are skipped while your freeze bank is full, so a shown ad always gives you something.
- No repeating goal ads: the goal-completion ad shows at most once per completed day, instead of returning on every app reopen.
Earlier releases
- Opening the garden is smooth: no stalls when you tap in from Today — the scene is prepared in the background and appears instantly.
- A calmer garden at rest: idle motion runs at a steady 60 fps, so mid-range phones keep up and the app does less work between frames.
- Fixed: the garden's Rate button no longer clips its label, and the title reads “Your Garden” when no name is set.
- The garden, rebuilt in depth: mountain ridges behind a pine treeline, living soil, a caustic pond, and real botanical detail for all six species.
- Weather you can feel: three-layer rain with ripples and splashes, and tumbling crystalline snow with a powder dusting.
- A garden that breathes: volumetric sun rays, a breeze through the canopy, bioluminescent night spores, and a celebration every time your plant grows.
- Quick species dock: switch between your unlocked companions with one tap.
- Gentler rating prompts: we ask at meaningful moments — and stay quiet for 30 days if you decline.
- Reminders, simplified: every reminder uses the same plain, friendly copy with quick-add buttons, on the interval you picked — 60 minutes by default.
- Rewarded ads return: reaching your daily goal and levelling up can show the rewarded ad for free users — and finishing the goal ad banks a Streak Freeze.
- Insights and History ads: the full-screen ad on those screens now shows, capped at one every 10 minutes.
- Fixed: the purchase screen could crash on some Android 14 devices, and stale widget taps could crash the app. Both are gone.
- Plain copy by default: the AI-written and quirky reminder pipelines were removed. Reminders use local, neutral copy — and the privacy policy spells out exactly which services receive anything.
- Streak Freezes: hit your goal 7 days running to bank a freeze (up to 3). Miss a day and one covers it automatically — your streak survives.
- Pause for 2 hours: a new action on every reminder, next to snooze. Back off without switching reminders off.
- Reminders that respect you: reminders cap at 8 a day, and swiping one away widens the gap instead of ignoring you.
- The garden, redrawn: a soft-pastel 2D illustration with layered depth and weather you can actually see.
- One-tap logging: the add and remove buttons beside your progress ring are always visible.
- Fixed: a billing hiccup could re-lock paid features for paying users. It no longer does.
- Garden rebuilt: a naturalistic garden with hand-drawn leaves, textured bark, real light and layered scenery — all six species grow through every stage.
- Built for tablets: a navigation rail on big screens, a two-pane History with your week beside the selected day, a two-column Today on 10" tablets, adaptive grids and centered layouts.
- Smoother garden: the scene is baked once per change instead of every frame, so it stays fluid.
- Nudges now work: fixed a configuration error that stopped the personalized reminder copy from being generated.
- Slump nudges fixed: the nudge that notices your usual afternoon dip now fires as designed.
- Tidier settings: removed an unused Health Connect option that was never functional.
- Widget crash fix: widget taps no longer crash after an app update — guarded action handling throughout.
- WorkManager crash fix: no more crashes on certain Samsung, Xiaomi and custom-ROM devices during background work.
- Play Billing crash fix: purchases degrade gracefully instead of crashing on devices with framework inconsistencies.
- Navigation stability: fixed a predictive-back gesture crash across all screens.
- Smart reminders: personalized reminder copy learned on-device from your own hydration history.
- Lifetime premium: a one-time purchase alongside the monthly and yearly plans.
- Localized reminders: greeting and goal-remaining copy translated across supported languages.
- Better interval labels: “Every hour” instead of “Every 1 hours”, with crash-safe formatting throughout.
- Accurate cloud totals: the Cloud Sync page shows your true lifetime entry count and volume.
- Plant growth overhaul: refined growth stages and progression for a more rewarding garden.
- Hydration windows: set active hours for reminders to fit your day.
- Enhanced atmosphere: realistic rain, fog and dynamic lighting in the garden.
- Smart goals: full support for kg/lb and ml/L/oz with real-time goal recalculation.
- Critical startup stability: resolved a StackOverflowError during initialization.
- Deep link notifications: support for dynamic links in push notifications.
- Defensive initialization: delayed analytics logging to prevent re-entrant loops.
- Persistent garden growth: plant growth scores now persist permanently across sessions.
- Hydration window: customizable daily drinking window for smart reminders.
- Smarter onboarding: a new time-picker dialog and subtle pulse animations.
- Unified unit display: volume formatting (ml, L, oz) consistent across all screens.
Surface · 0 m
Drink deep.
Live light.
Free on Android. No account. One tap to start — and a garden waiting at the end of the week.
Get Hydra on Google Play