Privacy Policy — TensiLog
Effective date: September 28, 2026 Developer: KnowVault (contact: dev@knowvault.net)
This Privacy Policy describes how TensiLog (the "App") handles your information. We have designed the App so that your health data never leaves your device.
1. What data the App collects
1.1 Data stored locally on your device (never uploaded)
- Blood pressure readings (systolic, diastolic, pulse, measurement time, arm/position notes you choose to add)
- Symptom notes and tags you enter
- App preferences and settings (units, reminders, display options)
- Generated Personal Health Summary documents, until you delete them or export them yourself
All of the above is stored in a local database on your device only. The App has no backend server, no cloud sync, and no upload functionality. We cannot access, read, or retrieve your health data under any circumstances — including if you ask us to.
1.2 Subscription transaction data (handled by RevenueCat)
The App offers an auto-renewing subscription. Purchase and subscription transactions are processed through RevenueCat, Inc. together with Google Play Billing. As a result:
- We do not receive or store your payment card details. Payment information (e.g., card number) is collected directly by Google Play, not by us or RevenueCat.
- RevenueCat processes purchase tokens and subscription status on our behalf. Per RevenueCat's own disclosures, this may include purchase history, which under Google Play's Data safety taxonomy falls under Financial info — Purchase history: data related to a purchase or transaction, collected for app functionality (analytics and subscription management), not shared with other parties beyond the processors named here, and not used for advertising.
- Your subscription is tied to your Google account. Managing or cancelling the subscription is done through Google Play.
1.3 Data we do NOT collect
- We do not collect your name, email address, phone number, or postal address.
- We do not collect precise or approximate location data.
- We do not use analytics SDKs, advertising SDKs, or tracking technologies.
- We do not sell, rent, or share your personal data.
2. Legal basis and purpose of processing
All locally stored data is processed solely on your device for the purpose of providing the App's core functionality: recording blood pressure and symptoms and generating a Personal Health Summary for you to share with a healthcare professional at your own discretion. The App does not provide medical advice, medical assessments, or treatment recommendations. It is a general wellness tool, not a medical device. Purchase data described in §1.2 is processed to deliver and manage the subscription you bought.
3. Data sharing and disclosure
Your health data is never shared, because it never leaves your device. The only third-party processor is:
| Processor | Data handled | Purpose | Policy |
|---|---|---|---|
| RevenueCat, Inc. | Purchase tokens, subscription status | Subscription verification and management | revenuecat.com/privacy |
| Google Play Billing | Payment details, transaction records | Payment processing (we never see card data) | policies.google.com/privacy |
4. Data retention and deletion
4.1 In-app deletion
You can delete your data at any time:
- Delete individual readings or symptom entries from within the App.
- Use Settings → Erase all local data to permanently delete all locally stored health data and preferences from your device. This action cannot be undone.
4.2 Web deletion request
If you have purchased a subscription and want to request deletion of data associated with your purchase, or want confirmation that no data about you is held on our side, use our web request page:
https://health.knowvault.net/tensilog/delete-request
Because the App is local-only and has no accounts or servers, we typically hold no identifiable data about you other than what RevenueCat retains as necessary for subscription records. Requests submitted via the page are handled by email; you can also write directly to dev@knowvault.net.
4.3 Subscription data
Subscription records held by RevenueCat and Google are retained per their own retention policies and your purchases' legal retention requirements. To cancel, use Google Play → Payments & subscriptions → Subscriptions.
5. Security
Your health data is stored in the App's local database in your app-private storage, protected by the Android operating system's sandboxing. Data in transit is not applicable to your health data (it is never transmitted). Payment security is handled end-to-end by Google Play.
6. Children's privacy
The App is not directed to children under 13 (or the equivalent minimum age in your jurisdiction), and we do not knowingly collect any personal information from anyone, since health data never leaves the device. If you believe a child has used the App, all data can be erased with one action per §4.1.
7. Changes to this policy
If we change this policy, we will update it at this URL and update the effective date. Material changes affecting data handling will also be announced in the App's release notes.
8. Contact
Questions, deletion requests, or privacy concerns:
KnowVault — dev@knowvault.net Web deletion request: https://health.knowvault.net/tensilog/delete-request