Mizu: Water Tracker is a daily hydration tracking app designed to help you build a simple, lasting habit. Record what you drink, track your progress, and watch your streak grow — day by day.
“Mizu” means “water” in Japanese. Simple. Clean. Effective.
Features
Record in Seconds
No typing, no sliders. Just tap your container and drink type — and you’re done. Choose from Cup, Mug, Bottle, or Glass, and pair it with Water, Coffee, Tea, Non-Alcohol Beer, and more. Every entry is logged instantly with a timestamp.
Daily Progress Ring
A clear circular progress ring shows exactly where you stand toward your daily hydration goal. Set your target in ml or fl oz — whichever you prefer.
Time-Block Goals (Pro)
Split your daily goal into Morning, Afternoon, and Evening targets. Get a gentle notification when you’re falling behind on a block.
Streak Heatmap (Pro)
A GitHub-style annual heatmap fills in blue for every day you hit your goal. The longer the streak, the harder it is to break.
Weekly & Monthly Charts (Pro)
Review your hydration trends over the past week or month with clean, easy-to-read bar charts.
Condition Memo (Pro)
Log a daily note about how you feel. Over time, you’ll start to notice the connection between hydration and your wellbeing.
Custom Reminders (Pro)
Set unlimited reminders throughout the day. Free users can set one fixed reminder.
Free vs Pro
| Feature | Free | Pro |
|---|---|---|
| Basic drink logging | ✓ | ✓ |
| Daily goal setting | ✓ | ✓ |
| Progress ring | ✓ | ✓ |
| ml / fl oz toggle | ✓ | ✓ |
| Weekly & monthly charts | – | ✓ |
| Annual heatmap | – | ✓ |
| Time-block goals | – | ✓ |
| Condition memo | – | ✓ |
| Custom containers & drinks | – | ✓ |
| Unlimited reminders | – | ✓ |
| Ad-free | – | ✓ |
Pro is available as a one-time purchase or annual subscription.
Developed by LINEOCEAN.
Terms of Service
Mizu: Water Tracker
Last updated: March 30, 2026
Please read these Terms of Service (“Terms”) carefully before using Mizu: Water Tracker (“the App”) operated by LINEOCEAN (“we,” “us,” or “our”).
By downloading or using the App, you agree to be bound by these Terms. If you do not agree to these Terms, please do not use the App.
1. Use of the App
Mizu: Water Tracker is a personal hydration tracking tool intended for general wellness purposes only. The App does not provide medical advice, diagnosis, or treatment. Content within the App is not a substitute for professional medical advice. Always consult a qualified healthcare provider regarding any health concerns.
You agree to use the App only for lawful purposes and in a manner consistent with these Terms.
2. Eligibility
The App is intended for users aged 4 and older. By using the App, you represent that you meet this age requirement. If you are under the age of 13, please ensure a parent or guardian has reviewed and agreed to these Terms.
3. In-App Purchases
The App offers optional paid upgrades to unlock Pro features. The following purchase options are available:
Lifetime Plan (One-Time Purchase)
A one-time payment that grants permanent access to all Pro features. This purchase does not expire and does not renew automatically.
Annual Subscription Plan
A recurring subscription billed once per year that grants access to all Pro features for the duration of the active subscription period. The subscription renews automatically unless cancelled at least 24 hours before the end of the current billing period.
All purchases and subscriptions are processed through Apple’s App Store and are subject to Apple’s Terms and Conditions. The following terms apply to both purchase types:
- Payment will be charged to your Apple ID account at confirmation of purchase.
- For the Annual Subscription, your account will be charged for renewal within 24 hours prior to the end of the current subscription period.
- You can manage or cancel your subscription at any time through your Apple ID Account Settings. Cancellation takes effect at the end of the current billing period; you will retain access to Pro features until that date.
- All purchases are final and non-refundable, except as required by applicable law or Apple’s refund policy.
- We reserve the right to modify pricing at any time. Price changes will be communicated in advance and will not affect active subscription periods already paid for.
4. Intellectual Property
All content, design, code, and trademarks within the App are the property of LINEOCEAN or its licensors. You may not copy, modify, distribute, or create derivative works based on the App without our express written consent.
5. Disclaimer of Warranties
The App is provided “as is” and “as available” without warranties of any kind, either express or implied. We do not warrant that the App will be uninterrupted, error-free, or free of viruses or other harmful components.
6. Limitation of Liability
To the fullest extent permitted by law, LINEOCEAN shall not be liable for any indirect, incidental, special, or consequential damages arising from your use of or inability to use the App, even if we have been advised of the possibility of such damages.
7. Changes to the App and Terms
We reserve the right to modify or discontinue the App at any time without notice. We may also update these Terms from time to time. Continued use of the App after any changes constitutes your acceptance of the new Terms.
8. Governing Law
These Terms shall be governed by and construed in accordance with the laws of Japan, without regard to its conflict of law provisions.
9. Contact
If you have any questions about these Terms, please contact us via the App Store page.
Privacy Policy
Mizu: Water Tracker
Last updated: March 30, 2026
LINEOCEAN (“we,” “us,” or “our”) operates the Mizu: Water Tracker app (“the App”). This Privacy Policy explains how we collect, use, and protect your information when you use the App.
By using the App, you agree to the practices described in this Privacy Policy.
1. Information We Collect
Information Stored Locally on Your Device
All hydration records, daily goals, condition memos, and settings you enter in the App are stored locally on your device only. We do not collect or transmit this data to our servers.
Information Collected Automatically
We use third-party services that may collect certain data automatically, including:
- Google AdMob — used to display advertisements to free users. AdMob may collect device identifiers, IP address, and usage data to serve relevant ads. This data is subject to Google’s Privacy Policy.
- Apple StoreKit — used to process in-app purchases. Purchase data is handled by Apple and subject to Apple’s Privacy Policy. We receive only confirmation of successful purchases.
App Tracking Transparency (ATT)
On iOS 14 and later, we request your permission before tracking your activity across apps and websites for advertising purposes, in accordance with Apple’s App Tracking Transparency framework. You may grant or deny this permission at any time via your device settings.
2. How We Use Information
We use the information described above solely for the following purposes:
- To provide and improve the App’s functionality
- To display advertisements to free users via Google AdMob
- To process and verify in-app purchases
We do not sell, rent, or share your personal information with third parties for their marketing purposes.
3. Data Retention
All user data (hydration logs, goals, memos) is stored locally on your device and remains under your control. Uninstalling the App will delete all locally stored data. We do not retain any personal data on our servers.
4. Children’s Privacy
The App is rated for users aged 4 and older. We do not knowingly collect personal information from children under the age of 13. If you believe a child under 13 has provided personal information through the App, please contact us and we will take appropriate steps to address the situation.
5. Third-Party Services
The App integrates the following third-party services, each governed by their own privacy policies:
- Google AdMob: https://policies.google.com/privacy
- Apple App Store / StoreKit: https://www.apple.com/legal/privacy/
6. Security
We take reasonable measures to protect the App from unauthorized access. However, no method of electronic storage or transmission is 100% secure. We encourage you to use your device’s built-in security features to protect your data.
7. Your Rights
Since all personal data is stored locally on your device, you have full control over your data at all times. You may delete your data at any time by clearing the App’s data or uninstalling the App.
If you have questions about data collected by third-party services (such as AdMob), please refer to those services’ respective privacy policies or contact them directly.
8. Changes to This Privacy Policy
We may update this Privacy Policy from time to time. We will notify you of any significant changes by updating the “Last updated” date at the top of this page. Continued use of the App after any changes constitutes your acceptance of the updated Privacy Policy.
9. Contact
If you have any questions about this Privacy Policy, please contact us via the App Store page.