Your day in water
From an empty tank
to full bloom.
Every morning starts with an empty tank, and your goal fills it. Spread your drinks through the day and your axolotl's gills open wider and brighter, until the whole tank glows.
For iPhone, iPad and Apple Watch
A water tracker
with a pet axolotl
Hydrolotl turns every glass you drink into a fuller tank and a happier axolotl. Log a drink in one tap, keep a gentle rhythm through the day, and watch your little friend glow.
- Free to use
- No ads
- No account
- Data Not Collected
How it works
Small sips add up to a whole little world.
Log a drink
Tap a glass in the app, on a widget, with Siri or on your Apple Watch. Water, tea, matcha, coffee, milk or sparkling water.
Fill the tank
Each drink raises the water in your axolotl's tank. Reach your daily goal and the tank is full to the brim.
Catch pearls, hatch friends
A drink of 150 ml (5 fl oz) or more blows a bubble. Drink again while it floats and it turns into a pearl.
From an empty tank
Pearls and eggs
Drink in rhythm,
meet someone new.
Pearls collect in the Nest, where an egg waits for your goal days. The more pearls it gathers before it hatches, the rarer the friend inside. There are 22 colour morphs to find, from wild and pink to the rare golden albino.
Make it home
A tank wider
than your screen.
Swipe along a tank that is several screens wide, and tilt your phone to make the water slosh. Spend pearls on plants, décor and bigger tanks, then arrange every piece yourself. Your axolotl will hide in them, swim through them and rest on them.
Night
When the lights go down,
some friends glow.
In the evening the tank turns soft and dark, and your axolotl settles in for the night. Some morphs glow in the dark. Tap the night light to give the water a new colour.
Your week
Every drink,
at a glance.
See today's drinks with their times, your progress towards the goal and how the last seven days went. Tea, coffee and milk count too. With Hydrolotl Plus you also get 30-day trends.
Apple Watch
Your tank,
on your wrist.
Log a drink without taking out your phone. The Watch shows your water, your pearls and your axolotl, by day and by night.
- Pour a drink with the Digital Crown
- Log with Double Tap
- Catch a pearl straight from a notification
- Keep the tank on a watch face complication
Log from anywhere
One tap, wherever you are.
Widgets
Home Screen and Lock Screen widgets show today's water and log a glass right where they are.
Live Activity
Your bubble waits in the Dynamic Island and on the Lock Screen, so you can see when the next drink catches a pearl.
Siri and Shortcuts
Say “Log a glass in Hydrolotl” when your hands are full.
Control Center and Action Button
Add a drink from Control Center, or put it on the Action Button.
Apple Health
Water and caffeine go to Apple Health, and water logged in other apps comes back in.
iCloud sync
Your log follows you between your iPhone and iPad, in your own private iCloud.
How much water?
A goal based on guidance,
not guesswork.
Health authorities give adequate intakes: amounts that cover the needs of most healthy adults. They count all water, from drinks and from food.
Hydrolotl suggests a goal that follows the European guidance, and you can change it. You need more in hot weather, when you exercise, and when you are pregnant or breastfeeding. Hydrolotl is not a medical app: if your doctor has given you a fluid limit, follow it and set it as your goal.
Kind by design
Miss a day? Nothing is lost.
No streaks to break
A missed day never resets your progress. Your axolotl is right where you left it, happy to see you.
Pearls can't be bought
Pearls come only from drinking. Hydrolotl Plus adds things to collect, but it never makes anyone grow faster.
Made for everyone
VoiceOver describes the whole tank in one clear sentence, Reduce Motion is respected, and the app speaks 34 languages.
Privacy
Your log is yours.
We never see it.
The App Store privacy label for Hydrolotl reads Data Not Collected. Your drinks stay on your device and, if you turn on sync, in your own private iCloud. There is nothing to sign up for.
- No account
- No ads
- No tracking
- Health data stays in Apple Health
Pricing
Free to track,
for as long as you like.
Hydrolotl Free
- Logging, reminders, widgets and Siri
- Apple Watch and the Live Activity
- Pearls, eggs, décor and bigger tanks, all earned by drinking
- Apple Health and iCloud sync
- No ads, ever
Hydrolotl Plus
- Rare morphs to hatch
- A new plant and décor pack every month
- 30-day trends
Monthly, yearly with a free week, or a one-time lifetime purchase.
The App Store shows the prices in your currency. Subscriptions renew until you cancel them in your Apple Account settings. Terms of use
Questions and answers
Is Hydrolotl free?
Yes. Tracking your water is free, with no ads and no time limit. Hydrolotl Plus is optional and adds rare morphs, a monthly plant and décor pack and 30-day trends.
What happens if I forget to drink for a day?
Nothing bad. Progress never resets, and your axolotl is waiting where you left it. The next drink picks up where you stopped.
Which drinks can I log?
Water, tea, matcha, coffee, milk and sparkling water. Hold a glass, mug or bottle to change its size.
Does Hydrolotl work with Apple Health?
Yes, if you allow it. Hydrolotl can save the water and caffeine you log to Apple Health and read water from it, so your totals match. Health data is never sent to us.
Do I need an Apple Watch?
No. Everything works on the iPhone alone. On Apple Watch you can pour with the Digital Crown, log with Double Tap and catch pearls from a notification.
Which devices does it run on?
iPhone and iPad with iOS 17 or later, and Apple Watch with watchOS 10 or later.
Blog
From the blog
How Much Water Should You Drink a Day?
EFSA's adequate intake is about 2 liters a day for women and 2.5 for men, food included. What it means, what raises it, and how to set your own goal.
Signs of Dehydration in Adults, Children and Babies
The common signs of dehydration in adults, children and babies, who is most at risk, what to do, and which symptoms mean you need help fast.
How to Drink More Water: Simple Habits That Stick
Practical ways to drink more water that are backed by health guidance: keep a bottle in sight, drink with meals, tie water to routines, give it time.
Press
Writing about Hydrolotl?
The press kit has the app icon and the App Store screenshots, and the key art pack has text-free illustrations. Both may be used in coverage of the app.
Press and partnerships: support@chili-logic.com
Your axolotl is waiting
for its first sip.
Free on the App Store for iPhone, iPad and Apple Watch.
Questions? support@chili-logic.com