Tenny — Privacy Policy
Last updated: July 6, 2026
Tenny ("the app", "we", "our") is an AI tennis-coaching app for iOS. This policy describes what data the app handles, where it lives, and what leaves your device.
In one sentence: your practice videos live on your phone and are analyzed there — except when you use cloud coaching, in which case the swing clip being coached is sent to Google's Gemini API for AI processing.
Who runs this app
Tenny is built by Zian Meng as an independent developer.
Contact: workingzian@gmail.com
Data we handle
Stored on your device
The following stays local, in the app's own storage:
- Videos you record in the app or import from your library (camera and microphone are used only while you record)
- The analysis computed from them — detected swings, pose skeletons, racket and ball tracking, swing metrics, grades, and coaching text
- Your session library, per-session notes, and app settings
Practice videos are deliberately excluded from iCloud/iTunes backups — they are large, re-recordable media. They never leave your device unless you use cloud coaching (below) or explicitly share/export a clip yourself.
Most of the analysis — finding every swing in a session, body-pose tracking, racket and ball tracking, swing-speed metrics — runs entirely on your device using Apple's Vision framework and bundled CoreML models.
Sent to Google (cloud coaching)
Tenny's richest coaching — a graded read of your swing with specific advice — is powered by Google's Gemini API. When a swing is coached in the cloud (the default for the graded coaching card; your free allowance and Tenny Pro both use it), the following is sent over HTTPS to generativelanguage.googleapis.com:
- A compressed copy of the swing clip being coached (video, with its audio)
- A coaching prompt (the instructions for the AI — no personal details in it)
We do not send your name, email, contacts, location, device identifiers, or any video you haven't asked the app to analyze.
Google's handling. According to Google's Gemini API terms: on the paid tier, Google does not retain prompts or responses beyond serving the request; on the free tier, Google may retain them for a limited period for abuse review and product improvement. Tenny uses whichever tier is configured at runtime.
Sent to YouTube (drill recommendations)
When Tenny recommends a practice drill video, it queries the YouTube Data API with a short search phrase derived from your coaching cue (for example, "tennis forehand extension drill"). No personal information is attached to the query. Watching a recommended video opens YouTube itself, which is governed by YouTube's terms and Google's privacy policy.
Subscriptions
Tenny Pro is sold through Apple's In-App Purchase system. Apple processes the payment; we never see your payment details. The app only learns whether an active entitlement exists. Your free-tier usage counter (number of cloud analyses used) is stored locally on your device.
Not collected at all
Tenny does not:
- Require or create user accounts — there is no sign-up in this version
- Operate a developer-run server that receives your data
- Use analytics SDKs (no Firebase, Mixpanel, Amplitude, etc.)
- Include advertising SDKs or trackers of any kind
- Sell, rent, or share your data with anyone
- Collect location, contacts, browsing history, or device identifiers
App Store privacy label
This is exactly what Tenny declares on its App Store "App Privacy" label (Apple's privacy nutrition label), and why:
| Category | Declared as | Why |
|---|---|---|
| Photos or Videos | Data Not Linked to You · App Functionality | Swing clips are sent to Google's Gemini API for cloud coaching. Sent without your identity; not used for tracking or advertising. |
| Audio Data | Data Not Linked to You · App Functionality | The clip's audio travels with the video for cloud coaching (it's also how contact moments are detected — that part happens on-device). |
| Everything else | Not collected | No contact info, identifiers, location, usage data, diagnostics, browsing, purchases data, or health data is collected. |
| Tracking | No tracking | No advertising SDKs, no analytics SDKs, no data shared with data brokers. The app never asks for App Tracking Transparency permission because it has nothing to track. |
Your rights and controls
You can at any time:
- Delete a session — remove it from your library (this deletes the video and its analysis)
- Delete everything — uninstall the app; all app data is removed with it
- Keep everything on-device — cloud coaching only runs for the graded coaching card; the rest of the app (recording, swing detection, overlays, your library) works entirely offline
- Export your clips — save analyzed clips to your photo library or share them wherever you choose
- Ask for help — email workingzian@gmail.com
For EU/UK residents (GDPR)
You have the right to access, correct, delete, or port your data, and to object to processing. Because Tenny does not operate a server, your data lives on a device you control — these rights are exercised directly through the app and your device. For anything you cannot resolve that way, email the contact address above.
For California residents (CCPA)
We do not sell your personal information. The categories described above are all we handle.
Children
Tenny is a general-audience sports app. It is not directed at children under 13, and we do not knowingly collect personal information from children under 13. A parent or guardian who believes a child's video was sent for cloud analysis can contact us to have any concern addressed.
Security
- Local data is stored in the app's sandbox, protected by iOS's file encryption
- All network requests (Gemini, YouTube) are made over HTTPS
- No developer-run server means no server-side database of your content to breach
No system is perfectly secure. If you discover a security issue, please email workingzian@gmail.com before disclosing it publicly.
Changes to this policy
If this policy changes, we will update the "Last updated" date at the top. Material changes will be surfaced in the app as well.
Contact
Questions about this policy or the app's data practices:
workingzian@gmail.com