Meet Mello: your friendly companion for understanding your body. Ditch the sterile scales. 100% free, privacy-first, and all data stored on your device.
Whether your goal is weight loss, maintaining your ideal body, or just keeping a daily diary of your health, Mello is the companion you've been looking for. Ditch the stressful, sterile apps. Mello uses a calming, beautifully crafted interface that makes logging your daily stats a relaxing habit, not a chore.
Instantly calculate your Body Mass Index and see exactly which category you fall into with our color-coded, easy-to-read gauge.
Visualize your weight data on a beautiful area chart. See your trend line move closer to your goal every week.
Logging your weight is satisfying. Use our custom scroll wheel to input measurements in seconds. No tedious typing required.
Based on your height and gender, Mello calculates your healthy weight range so you have a realistic, science-based goal.
Choose between metric (kg/cm) or imperial (lbs/ft) systems and set personal wellness goals. Mello adapts to you.
A friendly daily nudge to log your weight. Stay consistent and build healthy habits — no spam, just encouragement.
Download the app and start your journey today
Preview the app on your phone with Expo Go
Last updated: February 24, 2026
Mello ("we", "our", or "the app") is committed to protecting your privacy. This Privacy Policy explains how we handle your information when you use BMI Calculator & Weight: Mello (the "App").
The App collects the following personal data to provide its core functionality:
All your personal data is stored locally on your device only, using the device's built-in storage (AsyncStorage). Your data is never uploaded to our servers, cloud services, or any third-party infrastructure. If you delete the app, all your data is permanently removed.
We do not share, sell, rent, or transfer your personal data to any third parties. We do not use analytics services, advertising networks, or tracking SDKs that collect your data. Your health data stays exclusively on your device.
Your data persists on your device as long as the app is installed. You can delete all your data at any time through the app's Settings screen using the "Reset All Data" function. Uninstalling the app will also permanently delete all stored data.
The App may request permission to send you local push notifications as daily reminders to log your weight. These notifications are generated entirely on your device and do not involve any external servers. You can enable or disable notifications at any time through your device's system settings.
The App is not directed at children under the age of 13. We do not knowingly collect personal information from children. The App does not contain age-gated content or require account registration.
Because all data is stored locally on your device, you have full control over your information at all times. You can:
Under the General Data Protection Regulation (GDPR) and the California Consumer Privacy Act (CCPA), you have additional rights regarding your personal data. Since we do not collect, transmit, or store your data externally, these rights are inherently satisfied by the app's local-only data model.
We may update this Privacy Policy from time to time. Any changes will be reflected on this page with an updated "Last updated" date. We encourage you to review this policy periodically.
If you have questions or concerns about this Privacy Policy, please contact us at: mello@blytz.dev
Last updated: February 24, 2026
By downloading, installing, or using BMI Calculator & Weight: Mello (the "App"), you agree to be bound by these Terms of Use. If you do not agree to these terms, please do not use the App.
Mello is a personal health companion that allows you to calculate your Body Mass Index (BMI), log daily weight entries, track trends over time, and set wellness goals. The App is provided free of charge.
The App is not a medical device and does not provide medical advice. BMI calculations, healthy weight ranges, and any other health-related information provided by the App are for general informational purposes only. They should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider with questions about your health or before making changes to your diet, exercise, or health routine.
You are responsible for the accuracy of the data you enter into the App. The App's calculations and charts are only as accurate as the information you provide. You agree to use the App solely for personal, non-commercial purposes.
All content, design, graphics, and other materials within the App are the property of Mello and are protected by applicable intellectual property laws. You may not copy, modify, distribute, or create derivative works based on the App without our prior written consent.
The App is provided on an "as is" and "as available" basis without warranties of any kind, either express or implied, including but not limited to implied warranties of merchantability, fitness for a particular purpose, or non-infringement.
To the fullest extent permitted by applicable law, Mello and its developers shall not be liable for any indirect, incidental, special, consequential, or punitive damages, or any loss of data, use, or profits, arising out of or related to your use of the App.
You may stop using the App at any time by uninstalling it from your device. We reserve the right to modify, suspend, or discontinue the App at any time without notice.
We reserve the right to update these Terms of Use at any time. Changes will be posted on this page with an updated effective date. Continued use of the App after changes are posted constitutes your acceptance of the revised terms.
These Terms of Use shall be governed by and construed in accordance with applicable laws, without regard to conflict of law principles.
If you have questions about these Terms of Use, please contact us at: mello@blytz.dev
We're here to help. If you have questions, feedback, or need support with the Mello app, reach out to us anytime.
mello@blytz.dev