Privacy policy

Controller

The controller for the processing of personal data within the meaning of the General Data Protection Regulation (GDPR) is:

⚠ Daniel Kofler, sole trader — [street and number], [postal code] [city], Austria. Address to be filled in before publication.

Email: [email protected]

No data protection officer has been appointed; the conditions of Art. 37 GDPR are not met.

The short version

The text below explains this in detail, separately for the website and the app, because the legal situation differs.

This website

The public pages of this website consist exclusively of files generated in advance. There is no sign-in, no form, no shopping cart and no comment function. Two non-public paths run under the same address: the endpoint that receives feedback from the app, and a sign-in-protected internal area in which the provider reads that feedback. Neither is of any relevance to visitors of the website.

No cookies

Visiting the website sets no cookies and uses no comparable recognition techniques. That is why no consent banner appears — there would be nothing to consent to. A session cookie is set exclusively in the internal area, and only after the provider signs in. It is technically necessary for that sign-in and serves no recognition of visitors.

No analytics, no advertising

No analytics tools, tracking pixels, advertising networks or social network buttons are embedded.

No third-party content

Fonts, images and scripts are served by this website itself. No connection to third parties is established when a page is loaded.

When pages are requested, the web server processes technically necessary connection data (server log files): IP address, time, requested address, volume of data transferred, referring address and browser and operating system identifiers. This processing is necessary to operate and secure the website; the legal basis is Art. 6(1)(f) GDPR (legitimate interest in trouble-free and secure operation). This data is not combined with other sources, and no user profiles are created from it.

⚠ Enter the hosting provider and its registered office and, where required, confirm that a data processing agreement under Art. 28 GDPR is in place. Likewise the actual retention period of the server log files at that provider.

The MultiVolt app

The app opens a connection to the outside at exactly three places, and at no fourth. First, when you send feedback — see “Feedback from the app”. Second, the usage report, which runs at most once a day and which you can switch off — see “Usage reports from the app”. And third, at startup and on every return to the foreground the app asks whether a new version of the program code is available.

This update request transmits the running version, the platform and the identifier of the loaded program state. No data about you or your batteries goes out with it, but your IP address is visible to the update service — technically unavoidable, as with every request to an address on the network. The recipient is Expo (United States); see “Recipients and transfers to third countries”. The legal basis is Art. 6(1)(f) GDPR (legitimate interest in being able to fix faults promptly).

In particular, none of the following take place:

• Creation of a user account or sign-in
• Automatic transmission of crash or error reports
• Inclusion of advertising networks or identifiers for advertising purposes
• Determination or tracking of location
• Disclosure of the readings from your batteries
• Transmission of the names or installation locations you have assigned

The readings the app obtains from your batteries remain in the memory of the device and are discarded when the app is closed. They are neither stored permanently nor transmitted.

What is stored on your device

So that your setup survives a restart, the app stores two records in the protected app storage area on your device. The provider has no access to them.

Setup

Identifier, name, mounting location, colour, protocol and rated capacity of the configured batteries, whether they are wired in parallel, your thresholds and the demo mode switch. No measurements, no events, no history data.

Purchase state

The result of the last query to the App Store or Google Play: whether a subscription is active, which product, until when it runs and when it was last checked. This lets the app keep working when no network is available for weeks.

Both records are removed entirely when the app is deleted. Depending on your device settings they may be included in an operating system backup (iCloud or Google backup); the respective platform operator is responsible for that backup.

Bluetooth permission

The app needs Bluetooth to read the measurements from your batteries. Values are read only; no switching commands are sent to the battery.

On Android 12 and later the app requests the "find nearby devices" and "connect to nearby devices" permissions. The scan is explicitly flagged as not being used to derive location. On Android 11 and earlier the operating system technically requires the location permission for any Bluetooth scan; MultiVolt evaluates no location, stores none and transmits none.

The identifiers of discovered Bluetooth devices are used only to display them on the pairing screen and to find already configured batteries again.

Purchases and subscriptions

MultiVolt Pro is handled exclusively through the Apple App Store or Google Play. The purchase contract is concluded with the respective platform operator, not with the provider of this app.

For this purpose the app contacts the respective store to query available products, start a purchase, complete it and restore earlier purchases. Apple and Google process the resulting data on their own responsibility under their own privacy policies. The provider receives no information from the stores that identifies you as a person; it receives only aggregated sales and settlement reports.

• Apple: privacy policy of Apple Inc.
• Google: privacy policy of Google LLC

Feedback from the app

In the app you can report a battery, suggest a feature, report a fault or rate the app. This transmission is the only connection the app establishes to a server operated by the provider. It happens only when you tap “Send”. Before sending, you can expand a list on the same screen showing exactly what will be transmitted.

The legal basis is your consent under Art. 6(1)(a) GDPR. Tapping the button is the act of consent. You may withdraw your consent at any time with effect for the future and request erasure of what was received; an informal message to the email address given above is sufficient. The lawfulness of processing carried out until then remains unaffected.

The following is transmitted:

Always

The type of feedback, your text, the app version, the operating system and its version, the model designation of the device (for example “iPhone 15 Pro”) and the number of batteries set up in the app. For a rating, additionally the number of stars.

Only when reporting a battery

The Bluetooth name the battery module broadcasts itself, the identifiers (UUIDs) of the services it offers, and a short raw recording of what the module sends on its own. This information is required in order to support the battery at all. While doing so the app sends nothing to the battery, it only listens. An email address is also required here, because such reports are regularly unusable without follow-up questions.

Only if you add it yourself

An email address so that the provider can reply, and an image from your photo library. The app does not access photos on its own; you make the selection in the operating system’s own dialog.

The following is expressly not transmitted:

• the Bluetooth address or device UUID of your batteries
• the names and installation locations you gave your batteries yourself
• readings such as state of charge, voltage, current or temperature
• your location
• a device or installation identifier that would make you recognisable across several reports

If there is no connection when you send, the feedback stays on your device and is retried the next time the app starts — at most five entries, after which the oldest is dropped. An attached image is not sent later.

To prevent abuse, the server stores a keyed hash of the IP address in order to limit the number of entries per source. The IP address itself is not stored, and it cannot be recovered from the hash. The legal basis is Art. 6(1)(f) GDPR (legitimate interest in a functioning service).

The provider operates the server and the database itself. The content is not passed on to third parties and is not used for advertising, profiling or automated decision-making.

Usage reports from the app

At most once a day the app sends a short report on how it is being used and whether it works. The purpose is not audience measurement but fault-finding: otherwise the provider cannot see when a battery model goes unrecognised or a connection fails again and again — and whoever gets stuck there deletes the app and never gets in touch.

Transmitted is only:

• a random installation identifier (see below)
• app version, platform (iOS or Android) and major version of the operating system
• the number of configured devices, separated into batteries and solar chargers
• the battery protocols in use, such as “Ective” or “JK”
• the size class of the batteries, such as “100–199 Ah” — not the capacity you entered
• whether the bank is wired in parallel and whether thresholds have been changed
• whether demo mode is running and whether a subscription is active
• counters since the last report: app openings, connection attempts, successful connections, failures by cause, decoding errors
• how often which kind of alarm was raised, such as “state of charge” or “cell too warm”

Not transmitted are: the names and installation locations you assigned, the Bluetooth addresses of your devices, any individual reading (voltage, current, state of charge, temperature), your location and the language you have set.

The installation identifier

A random number that the app generates itself and stores on your device. It is not derived from device properties, is not an advertising identifier and cannot be matched with any other app. It serves solely to add up the reports of one installation instead of counting every report as a new user. In legal terms it is therefore pseudonymous data and not anonymous — which is why this section exists. The identifier is reassigned if you delete and reinstall the app; resetting the configuration does not change it.

Legal basis

Art. 6(1)(f) GDPR. The legitimate interest is finding faults in an app that drives hardware the provider does not own. Set against this are reports that contain neither content nor readings and identify no person. You may object to this processing at any time under Art. 21 GDPR — the switch in the settings is exactly that objection and takes effect immediately.

Abuse prevention

As with feedback, the server stores a hash of the IP address formed with a secret in order to limit the number of reports per source. The address itself is not stored.

The reports are held solely on a server operated by the provider within the European Union. They are not passed on to third parties, not used for advertising and not combined with other sources. Individual reports are deleted after 90 days, an installation after 180 days without a sign of life.

Recipients and transfers to third countries

No data from your use of the app is passed on to third parties. Feedback you send yourself resides exclusively on a server operated by the provider and is not passed on. The hosting provider is involved as a processor in the operation of the website and of that server. No external mail delivery service is used to notify the provider of incoming feedback.

One exception is the app’s update request: it is addressed to Expo (650 California St, San Francisco, CA 94108, United States). It transmits the app version, the platform and the identifier of the loaded program state; your IP address is visible to the service in the process. No further data goes with it. The United States is recognised as a safe third country by the adequacy decision of the European Commission of 10 July 2023 (EU-US Data Privacy Framework), insofar as the recipient has subjected itself to that framework.

Beyond that, the provider does not transfer data to countries outside the European Economic Area. Whether and where Apple or Google transfer data in the course of processing purchases is governed by their own terms.

Your rights

You have the following rights vis-à-vis the controller, insofar as the statutory requirements are met:

• Access to the data processed (Art. 15 GDPR)
• Rectification of inaccurate data (Art. 16 GDPR)
• Erasure (Art. 17 GDPR)
• Restriction of processing (Art. 18 GDPR)
• Data portability (Art. 20 GDPR)
• Objection to processing based on legitimate interest (Art. 21 GDPR)

In practice this concerns the server log files of this website, any feedback you have sent yourself, and the usage reports from your installation. The provider holds no other personal data. An informal request to the email address given above is sufficient; if you sent feedback without an email address, please state the approximate time and content so that it can be identified. For usage reports, please give your installation identifier — it is shown in the app settings under “Usage reports”; without it the reports cannot be attributed and therefore neither disclosed nor selectively deleted.

Irrespective of this, you have the right to lodge a complaint with the supervisory authority. The competent authority is the Austrian Data Protection Authority, Barichgasse 40–42, 1030 Vienna, [email protected].

Retention period

Server log files of the website are kept only as long as necessary for operation and security and are deleted afterwards. The setup stored on your device remains until you remove it in the app or delete the app. Feedback is deleted once the matter has been dealt with, and at the latest 24 months after receipt; attached images are deleted with it. Usage reports are deleted 90 days after receipt; the aggregated state of an installation is deleted once no report has arrived for 180 days. The hash values used for abuse prevention are removed after at most two days.

Children

The app is not directed at children. It collects no data on its own; the only thing transmitted is what someone sends as feedback themselves. The age requirements of the respective store apply to taking out a subscription.

Changes to this policy

This policy is adjusted when the app, the website or the legal situation changes. The version published here is the applicable one; the date of the last change is shown above.