Privacy Policy
Effective October 5, 2026 · Last updated October 30, 2026
Your training is personal. This policy explains what Kalstheno handles, where it is stored, and the choices you have.
Kalstheno is an iOS calisthenics training app developed and operated by Dipanshu, based in India. This policy covers the Kalstheno app, this website, and support correspondence. For privacy questions, contact contact@kalstheno.com.
1. Information you keep in the app
Kalstheno does not require a Kalstheno account or sign-in. It uses information you enter or generate while training to build your plan, guide sessions, adjust progression, and show your history:
- Profile and preferences: your name, an optional profile photo, approximate birth year derived from the age you enter, gender or body-diagram preference, training experience, goals, target skills, equipment, schedule, and unit preferences.
- Training records: plans and program blocks, saved sessions, exercise and set logs, repetitions, hold times, distance or load where applicable, effort ratings, skill tests, levels, personal records, milestones, and notes.
- Fitness and health-related entries: body weight, joint cautions, health-screen answers, pain flags, and readiness ratings for sleep, soreness, joint status, and motivation.
- Photos: progress photos you choose to capture or import, along with their date, pose, and any note you add.
Coaching decisions are made in the app. Kalstheno does not send these training records, health entries, or photos to a developer-operated server, to RevenueCat, or to an external AI service. We do not have remote access to your private training database.
2. Device storage and private iCloud sync
Your app records are stored on your device. When iCloud is available for Kalstheno, the app uses Apple’s CloudKit service to synchronize its database through your private iCloud account across your devices. If iCloud is unavailable, the app can use local storage.
This is your private iCloud data, not a public database or a social feed. Apple operates iCloud and applies its own storage, security, and account policies. We do not claim that all processing happens only on your device: iCloud synchronization transfers app records to Apple’s service.
In the current app, the synchronized records include body-weight entries and the health-related entries described above. Body weight imported from Apple Health is also saved in this app database; see the Apple Health section.
3. Profile and progress photos
Photos are optional. The app uses the system photo picker for images you select and asks for camera permission when you choose to take a progress photo.
Imported or captured photos are resized or cropped and re-encoded before storage. Original EXIF metadata, including GPS location, is not retained in the stored copy. Dates, poses, and notes you enter separately are still kept as app records.
Progress photos are stored on your device and in your private iCloud, never uploaded to a Kalstheno-operated server or analysed by Kalstheno. They leave the app for sharing only when you choose to share a comparison through the system share sheet. The recipient or service you choose then controls that shared copy under its own privacy practices. Sharing does not delete the private original.
4. Optional Apple Health access
You can use Kalstheno without connecting Apple Health. If you connect it and grant the relevant system permissions, Kalstheno:
- Reads body weight from Apple Health to update your weight history and body-weight-based training levels.
- Writes body weight you log in Kalstheno to Apple Health after you connect it.
- Writes completed workouts to Apple Health, including start time, end time, and workout type, with identifiers needed to avoid duplicate writes.
The app does not request access to heart rate, sleep records, location, or other Health categories. Sleep and soreness readiness ratings are answers you enter in Kalstheno, not records read from Apple Health.
Imported body-weight values become Kalstheno records and, in the current implementation, can synchronize through the app’s private iCloud database. They are not sent to RevenueCat, used for advertising, sold, or shared with a developer-operated health-data service.
Turn off the connection in Profile → Apple Health to stop further syncing on that device. Manage or revoke system permissions in Apple Health or your device’s privacy settings. Turning the connection off does not automatically delete existing app entries or records already written to Apple Health. Apple Health records are managed separately in the Health app.
5. Purchases and RevenueCat
Apple processes App Store purchases and payments. Kalstheno and RevenueCat do not receive your payment-card details.
Kalstheno uses RevenueCat to display subscription offerings, validate purchases, restore access, determine whether Kalstheno Pro is active, and report subscription performance. The app configures RevenueCat with an automatically generated app-user identifier instead of a name or email address.
RevenueCat processes that identifier, purchase and subscription history, transaction or receipt information, subscription status, and relevant app and device technical information, such as device type and operating system. Network requests also expose connection information such as an IP address to the receiving service. “Anonymous identifier” does not mean that no data is processed.
The developer can see subscription records and aggregate subscription reporting in RevenueCat. The app does not attach your profile name, email, training logs, photos, or Apple Health data to those records, and no advertising or additional analytics integrations are enabled for launch.
For provider information, see RevenueCat’s Privacy Policy and Apple’s Privacy Policy. Their records and retention obligations are separate from your on-device app database.
6. Reminders and device permissions
If you allow notifications, Kalstheno schedules local training reminders and rest alerts on your device. These reminders do not require a separate messaging or advertising service. Permission is optional and can be changed in device settings.
Camera, photo-selection, Health, and notification access are used for the features you choose. The app does not request location, contacts, microphone, or advertising-tracking permission. This website adds no analytics scripts, signup forms, advertising trackers, or cookies of its own.
7. Website visits and support email
This website is hosted by GitHub Pages. GitHub logs visitors’ IP addresses for security purposes, whether or not they are signed in to GitHub. See GitHub Pages data collection and GitHub’s Privacy Statement.
If you email support, we receive your email address, your message, and any information or attachments you choose to provide. We use this information to answer your request, troubleshoot issues, and handle privacy or purchase questions. The support mailbox uses Gmail, operated by Google; see Google’s Privacy Policy.
Send only what is needed to explain the issue. You do not need to send progress photos, medical records, payment-card information, or your Apple Account password. Support messages are not used for marketing mailing lists.
9. Retention and security
App records remain on your device and, where enabled, in your iCloud until you remove them or manage the app’s stored data. Deleting the app removes its local installation but does not necessarily remove iCloud data, backups, Apple Health records, subscription records, or copies you have shared.
Support correspondence is kept only as long as reasonably needed to resolve requests, maintain necessary support records, and meet legal obligations. Apple and the other providers determine retention for records held by their services, including transaction, security, and backup records.
Kalstheno relies on iOS storage protections and the security mechanisms of its providers. No storage system or network service can be guaranteed completely secure.
10. Your choices and privacy rights
- Edit supported profile and training preferences in the app. Remove a profile photo from Profile or delete a progress photo from its viewer.
- Delete a saved custom session from its menu in My sessions. This removes the reusable session, but keeps completed workouts and personal records in your history. Supported record deletions synchronize to iCloud when sync is available; shared or exported copies are not recalled.
- Manage Kalstheno’s iCloud data through your Apple Account’s iCloud storage controls. Check Apple’s settings before removing data you want to keep.
- Revoke optional permissions in device settings or Apple Health. Manage records already written to Health in the Health app.
- Manage or cancel subscriptions through your Apple Account. Removing app data or the app itself does not cancel a subscription.
Depending on your location and applicable law, you may have rights to request access, correction, deletion, restriction, portability, objection, or withdrawal of consent for personal information processed about you. Contact us to exercise applicable rights or make a privacy complaint. You may also be entitled to contact your local data-protection authority.
We can assist with information we actually hold, such as support correspondence and relevant subscription records. We cannot remotely retrieve or delete training records or photos in your private device and iCloud storage. There is no Kalstheno account to delete, and the app does not currently provide a single “delete all data” button. Provider retention and legal requirements may limit some deletion requests.
11. Young users
Kalstheno is intended for people aged 13 and older and is not directed to children under 13. Users who are minors under the law where they live must have a parent or guardian’s permission and supervision, including for purchases and any consent required by local law. A device permission prompt does not replace any legally required parental consent.
If you believe a child has provided personal information to us without the required permission, contact us so we can address information we hold and explain how to remove device or iCloud records. We do not claim that guardian permission alone satisfies every country’s requirements for children’s data.
12. Policy changes
We may update this policy when the app, its providers, or applicable requirements change. The date at the top identifies the latest version. Material changes will be communicated through the app or another appropriate notice where required.
13. Contact
Dipanshu · India
Privacy and support: contact@kalstheno.com
For practical help with subscriptions, permissions, and deletion, visit Kalstheno Support.