Privacy notice

In short

We do not collect a serial number, an IMEI, an email address or a name. There is no user account. The uploaded screenshot is processed in memory only and discarded immediately after the values have been read — it is never stored. Manufacture and first-use dates are kept to the month, because that is the precision iOS shows on that screen. We set no advertising or tracking cookies, which is why there is no consent banner.

Controller

The controller within the meaning of the GDPR is named in the imprint.

What is processed

• Read from the screenshot: maximum capacity, charge cycle count, manufacture month, first-use month, detected language.
• Provided by you: the device model and, optionally, the iOS version.
• Collected technically: a coarse country of origin from Cloudflare geolocation, the time of submission, and a one-way digest of the image used to detect repeat submissions.
• Optional, and only on an explicit action: a randomly generated recovery code, of which the server stores only a hash formed with a secret key.

What is deliberately not processed

• No serial number and no IMEI. The Battery Health page does not contain them, and we deliberately never ask for the About page.
• No plaintext IP address in our database. For abuse prevention the IP address is used transiently and in hashed form only.
• No day-level date for manufacture or first use — iOS only ever shows month and year there. The time of submission is recorded precisely, because the time series is what makes the dataset worth anything.
• No storage of the image, not even temporarily on disk.

Legal basis

Processing of submitted readings rests on Art. 6(1)(f) GDPR. Our legitimate interest is building a meaningful, open comparison dataset on battery ageing. Because the stored dataset contains nothing that can be attributed to an identified person, the interference is minimal. Processing for abuse prevention likewise rests on Art. 6(1)(f) GDPR.

Image processing via Cloudflare Workers AI

To read the values, the screenshot is passed to an image-recognition model operated inside Cloudflare’s infrastructure. The image is not permanently stored there and is not used for training. After extraction it is discarded.

Processors

Hosting, database, image recognition and bot protection run on Cloudflare, Inc. A data processing agreement is in place; transfers to third countries are covered by the EU Standard Contractual Clauses.

Bot protection

To prevent automated bulk submissions we use Cloudflare Turnstile. Turnstile works without recognition cookies and without building a cross-site behavioural profile.

Browser storage

In your browser’s local storage we keep only your chosen language and — if you generated one yourself — your recovery code. You can remove both at any time via your browser settings or the button on the “My device” page.

Retention

The anonymised readings are kept indefinitely, because the value of a degradation dataset lies precisely in its long time series. Screenshots are not retained. Abuse-prevention counters expire automatically after at most one hour.

Your rights

You have the right of access, rectification, erasure, restriction of processing, data portability and objection, as well as the right to lodge a complaint with a supervisory authority. One practical note: because we deliberately collect nothing that identifies you, we cannot attribute a submission to a person without your recovery code. With the code you can view and delete your own entries on the “My device” page.

Sharing and analysis

Aggregated or anonymised analyses may be produced from the dataset and made available to third parties. Because the dataset contains no personal reference, this is not a transfer of personal data.