PRIVACY Last updated: May 27, 2026

Overview

HUNDREDWEIGHT is a fitness tracking app developed by a solo independent developer. Your privacy is taken seriously. This policy explains what data the app accesses, how it's used, and how it's stored.

Data Collection and Storage

HUNDREDWEIGHT stores your workout data, routines, settings, history, and body composition logs locally on your device. There are no HUNDREDWEIGHT-operated servers, no analytics services, and no advertising trackers.

iPhone / iPad: HUNDREDWEIGHT uses Apple's CloudKit service to automatically sync your data to your personal iCloud account so it can restore on a new device. This data is encrypted by Apple, stored in your private iCloud database, and is not accessible to HUNDREDWEIGHT or any third party.

Android: Because Android does not have a free per-user private cloud database equivalent to iCloud, HUNDREDWEIGHT uses Google Firebase (Authentication and Cloud Firestore) to provide cross-device sign-in and cloud sync. Your email address is collected to identify your account, and your workout data, routines, history, settings, and body composition logs are stored in a HUNDREDWEIGHT-owned Firestore database. Access is restricted by Firebase security rules so that only you, signed in with your account, can read or write your records. Google acts as a data processor; HUNDREDWEIGHT is the data controller. Google's Firebase data handling is governed by the <https://firebase.google.com/terms/data-processing-terms>. Data is encrypted in transit (TLS) and at rest by Google.

HealthKit (iPhone / iPad)

HUNDREDWEIGHT integrates with Apple HealthKit to:

• Read body weight and body fat percentage data (e.g., from smart scales like Withings)

• Read heart rate data during workouts (e.g., from Apple Watch or AirPods Pro 2)

• Read daily activity metrics — active calories, steps, walking heart rate, heart rate recovery, VO₂ Max, and blood oxygen — populated by Apple Watch, Garmin, Oura, WHOOP, iPhone, and similar devices. These are displayed on the Stats page so you can see day-over-day health context alongside your training.

• Read overnight recovery metrics — sleep analysis, heart rate variability (HRV), resting heart rate, and respiratory rate — populated by any device that syncs to Apple Health (Eight Sleep, Apple Watch, Oura, WHOOP, Garmin, Withings, and similar trackers). These are displayed on the Stats page so you can see recovery context alongside your training.

• Write completed workouts, active energy burned, and workout distance back to Apple Health so they appear in your Activity rings and workout history.

HealthKit data is used solely to display and save metrics within the app. Health data obtained through HealthKit is processed entirely on your device, is not shared with third parties, is not sold, is not used for advertising, and is not transferred to any external service. Access to HealthKit requires your explicit permission and can be revoked at any time in your device's Settings under Privacy & Security → Health.

Health Connect (Android)

HUNDREDWEIGHT integrates with Google Health Connect to:

• Read body weight and body fat percentage data (e.g., from smart scales that sync to Health Connect like Withings, Garmin, or Fitbit)

• Read heart rate data during workouts (from Bluetooth heart rate monitors, Wear OS watches, and other devices that write to Health Connect)

• Read active calories so the in-app value matches the active-calorie samples HUNDREDWEIGHT itself writes for completed workouts

• Write completed workouts, active calories, and heart rate samples back to Health Connect so they appear in your activity history and other connected apps

Health data obtained through Health Connect is processed on your device for display, and workout data (along with the heart rate samples captured during your workouts) is also written to your HUNDREDWEIGHT account in Cloud Firestore (see Data Collection and Storage above) so it can sync across devices. Health data is not sold, is not used for advertising, and is not shared with any third party other than Google as the operator of Cloud Firestore. Access to Health Connect is per-category and requires your explicit permission. You can revoke access at any time in Health Connect under HUNDREDWEIGHT's app permissions.

Recovery and Daily Health stats (sleep, HRV, resting heart rate, respiratory rate, steps, and blood oxygen) are available on iPhone / iPad through Apple HealthKit but are not read on Android, as those data types fall outside Google's approved Health Connect use cases for a weightlifting tracker.

Bluetooth

HUNDREDWEIGHT uses Bluetooth to connect to external heart rate monitors during workouts. Bluetooth data is processed locally and is not transmitted or stored beyond the active workout session's heart rate readings, which are saved to your on-device workout history (and, on Android, synced to your HUNDREDWEIGHT account in Cloud Firestore alongside your other workout data).

On Android 12 and later, this requires the "Nearby devices" permission. HUNDREDWEIGHT does not use Bluetooth scanning to derive your physical location.

Notifications

HUNDREDWEIGHT uses local notifications to alert you when rest and warm-up timers complete and to keep a workout-active notification visible while you train. These notifications are generated entirely on your device and do not involve any external push notification service.

On Android, HUNDREDWEIGHT may request to be exempt from Battery Optimization so that timer alerts fire reliably while the screen is locked. This permission is requested with your consent during the first-run setup, and you can revoke it at any time in Android Settings → Battery.

Over-the-Air Updates

HUNDREDWEIGHT delivers in-app updates (bug fixes and small feature changes) through Capgo, a third-party over-the-air update service. To check for updates, your device sends a minimal request containing the app version, a randomly-generated device identifier created by Capgo, and your platform (iOS or Android). Capgo does not receive any of your workout data, health data, account email, or any other personal information. See <https://capgo.app/privacy> for details.

Data Retention

HUNDREDWEIGHT retains your data only as long as it serves the purpose for which it was collected:

• Local data: workout history, routines, settings, and body composition logs are stored on your device for as long as the app is installed. Uninstalling the app removes all locally stored data.

• iCloud-synced data (iPhone / iPad): retained in your private iCloud database for as long as your iCloud account remains active. This data is managed entirely by Apple; HUNDREDWEIGHT has no access to or control over its retention.

• Firebase-synced data (Android): your email address (used as your account identifier) and synced workout data, routines, history, body composition logs, and master notes are retained in HUNDREDWEIGHT's Cloud Firestore database for as long as your HUNDREDWEIGHT account remains active. If you delete your account through the in-app option (see Data Deletion below), this data is permanently and immediately removed.

• Health data: HUNDREDWEIGHT does not retain health data obtained from HealthKit or Health Connect beyond the active session in which it is displayed. Workouts and metrics that HUNDREDWEIGHT writes back to HealthKit or Health Connect remain in those systems and are managed by you through Apple Health or Health Connect directly.

Data Deletion

You can delete your data at any time using any of the following methods:

• Delete your HUNDREDWEIGHT account (Android): open HUNDREDWEIGHT → Settings → Account → DELETE ACCOUNT. Enter your password to confirm. This permanently and immediately removes your Firebase account, your email record, every workout, routine, PR, body composition log, and master note from HUNDREDWEIGHT's Cloud Firestore database, and every record stored on your device. You will be signed out and returned to the sign-in screen.

• Clear all in-app data: open HUNDREDWEIGHT → Settings → Clear All History. This permanently removes every workout, PR, and session record stored on your device. On Android, the corresponding cloud-synced records are also removed from your HUNDREDWEIGHT account in Cloud Firestore.

• Uninstall the app: removing HUNDREDWEIGHT from your device deletes all local data. Note that uninstalling alone does not delete cloud-synced data — use the in-app options above or the system options below to remove cloud-synced data.

• Delete iCloud-synced data (iPhone / iPad): open iOS Settings → [your name] → iCloud → Manage Account Storage → HUNDREDWEIGHT → Delete Data. This permanently removes HUNDREDWEIGHT's data from your private iCloud database.

• Delete data written to HealthKit (iPhone / iPad): open iOS Settings → Health → Data Access & Devices → HUNDREDWEIGHT → Turn Off All Categories, then tap Delete Data From HUNDREDWEIGHT. This removes any workouts, calories, or heart rate samples HUNDREDWEIGHT wrote to Apple Health.

• Delete data written to Health Connect (Android): open the Health Connect app → App permissions → HUNDREDWEIGHT → Delete app data. This removes any workouts, calories, or heart rate samples HUNDREDWEIGHT wrote to Health Connect.

• Email request: if for any reason you cannot use the options above, you can email support@hundredweightapp.com from your account address with the subject "Delete Account." Deletion requests will be actioned within 30 days.

Third-Party Services

HUNDREDWEIGHT uses the following third-party services. None of them are used for analytics, advertising, or behavioural tracking:

• Apple iCloud / CloudKit (iPhone / iPad only) — for syncing your data to your private iCloud database.

• Google Firebase Authentication (Android only) — for email/password sign-in.

• Google Cloud Firestore (Android only) — for storing your workout data so it can sync across devices.

• Google Health Connect (Android only) — for reading and writing health data on your device.

• Apple HealthKit (iPhone / iPad only) — for reading and writing health data on your device.

• Capgo (both platforms) — for delivering over-the-air app updates.

No data is shared with or sold to advertisers or third-party data brokers.

Children's Privacy

HUNDREDWEIGHT does not knowingly collect information from children under the age of 13.

Changes to This Policy

This privacy policy may be updated from time to time. Any changes will be reflected on this page with an updated revision date.

Contact

If you have questions about this privacy policy, please contact: support@hundredweightapp.com