Privacy Policy

1Who we are

Molveth is an offline periodic table, practice and chemistry-calculation app for students, teachers and curious adults, developed by Zydeno. This policy explains what happens to your notebook, practice history and settings, and what happens if you choose to contact us at [email protected].

2What this policy covers

This policy covers the Molveth Android app. It does not cover the independent document providers, apps, print services, printers, browser or e-mail service you choose to use. Their own terms and privacy policies govern the data you give them.

The app works without an account or an internet connection. The app has no ads and no analytics.

3What the developer does not collect

The app does not send the developer your formulas, equations, calculation inputs or results, worksheet notes, practice answers, study schedule, settings or device information. It has no account registration, no advertising SDK, no analytics SDK and no third-party crash reporter, and it does not request location, contacts, camera, microphone, phone or storage-wide access.

We do not receive, sell or share your in-app data, use it for advertising or train models on it. Molveth does not ask for your name, age, school or class, and does not rank you against other people. If you type a real name or other personal information into a worksheet title or note, it stays part of your private notebook until you choose to export, share or print it.

4Study data on your device

Molveth stores its working data in Android app-private storage (a preferences store and local files). Depending on how you use the app, this includes:

• Saved worksheets: the formulas, equations, quantities, units and options you entered, the calculated result and its working, the dataset version used, titles, optional notes and dates.
• Practice data: the element scope you chose, answers, outcomes, review dates and the spaced-repetition schedule, and optional session history.
• Your last table position and selections, pinned elements, recent searches and unfinished drafts, so the app can resume where you left off.
• Settings: language, units for each quantity, theme, motion, haptics, optional sound and volume, number-precision and table-form choices.

The element data, models, help text and practice questions are bundled in the app and are read-only. All searching, calculation, practice scheduling, rendering and export generation run on your device. Region and language are used only to choose defaults (see Permissions and device access).

5No internet access from the app

The current Android app does not declare the INTERNET permission. It has no backend, external API requests, automatic uploads, remote data downloads or cloud synchronisation. The periodic table, calculation models, reference text and practice questions are bundled in the app.

When you open a link (this policy, the Terms, a data-source page or a support e-mail address), the app hands the address to your own browser or e-mail app. Your browser then visits the site, and the website host can process ordinary web-request data such as your IP address under its own policy. Nothing is sent by Molveth itself, and a support e-mail is sent only if you choose to send it. Document providers, share recipients and print services can use their own network access as described below.

6Manual export, import, sharing and printing

Full backup. In Settings you can save a complete archive (a JSON file) through Android’s Storage Access Framework, the system document picker. It contains your saved worksheets, practice records and schedule, and settings, with format and integrity information. It is a copy of your private study data and is not password-encrypted by Molveth.

Import. Only the archive you select in the system picker is read. The app validates it locally and shows a preview before you confirm. Importing does not send the archive to Zydeno.

Worksheets and reference sheets. You can generate a PDF of a worksheet or a reference table and save it to a destination you choose, print it, or use Android’s share sheet to send a PDF or a text summary of a calculation to another app. Sharing passes the selected file or text to the app you choose through Android’s FileProvider or a standard share intent; it does not grant access to the rest of your notebook. Temporary PDF files may remain in the app cache until Android or the app clears them.

Printing. When you choose Print, the document is passed to Android’s print framework and your selected print service and printer. These may transmit the document over a network, retain print jobs or use a cloud service. Check their privacy settings before printing a worksheet that contains personal notes.

Your destination matters. The system picker can offer local storage or a cloud document provider. A cloud provider, recipient app or printer receives the file you choose to give it, under its own policy. This is a user-directed transfer, not automatic synchronisation. Zydeno receives no copy unless you deliberately send one to support.

7Permissions and device access

The current app does not request internet, location, microphone, camera, contacts, phone, notification, storage-wide, all-files or Accessibility-service access. Android also adds an app-scoped internal permission used by its support libraries; it does not grant access to your personal files or sensors, and the advertising-ID permission is removed from the app.

Region. To choose sensible default units, paper size and number formats, the app reads your device’s region locally: the country reported by your SIM or network through Android’s standard telephony information (no permission is needed and no phone number or subscriber identifier is read) and the region of your system language. This value is used on the device only; it is not transmitted to us or anyone else, and you can change every unit in Settings.

Haptics and sound. The app uses your phone’s standard haptic feedback, which you can switch off in the app or in Android. Optional short interface sounds are bundled with the app, are off by default and play only if you switch them on and the phone is not in silent or do-not-disturb mode. The app does not record audio.

The system file picker gives access only to the specific document you choose. Android sharing and printing involve only the file or text you select.

8Your controls, backups and deletion

You can review and delete saved worksheets and practice records in the app, reset the practice schedule, clear practice history, change every setting, export a full archive, and use Settings, Your data, Delete all to remove saved notebook, practice and settings data after a separate confirmation. Export an archive first if you want to keep your work.

Automatic Android backup is disabled and the app’s extraction rules exclude cloud backup and device-to-device transfer. To move your study data to another phone, save a manual archive and import it yourself. If the device is lost or app storage is cleared without a usable archive, the developer cannot restore your data.

Clearing Molveth’s storage in Android Settings or uninstalling it removes app-private data, including temporary files. Deleting records in the app does not delete copies you saved elsewhere, files received by another app, print jobs or paper copies; remove those separately at their destinations.

9Legal bases for processing

Where the EU or UK GDPR, or a similar law such as the Swiss FADP or Brazil’s LGPD, applies, these are the legal bases for the limited processing described in this policy:

The app makes no automated decisions that have legal or similarly significant effects on you, does not build a profile of you and does not analyse special categories of personal data. Notes you type into a worksheet are your own text; they stay on your device unless you export, share or print them, and the developer receives none of them.

10How long information is kept

Saved app data stays on your device until you remove it, clear app storage or uninstall the app. Interrupted-work drafts and pre-restore snapshots support recovery; deleting a visible item is not a guarantee of forensic erasure of every historical byte on the device.

Generated PDFs, share files and import staging files may remain in the app cache until Android or the app clears them. Documents you saved through the system picker remain under your control outside the app and may outlast uninstallation.

11Your privacy rights

Privacy laws in many countries give you rights over your personal data. Because Molveth keeps your data on your phone and the developer does not receive it, most of these rights are in your own hands: you can view, correct, export and delete everything in the app (§8) and withdraw permissions in Android Settings. For data you have sent us, such as e-mails, write to [email protected].

EU and UK representative. The individual developer does not process personal data of people in the EU/EEA or the UK except occasional e-mails you choose to send to support. This occasional processing does not involve large-scale processing of special-category or criminal-offence data and is unlikely to result in a risk to your rights and freedoms. Under Article 27(2)(a) GDPR and Article 27(2)(a) UK GDPR, it does not require an EU or UK representative, so none is appointed. Contact us directly at [email protected]; you can also complain to your local supervisory authority.

Rights by region. A summary; the law where you live decides the details.

• European Union, EEA, United Kingdom and Switzerland (GDPR, UK GDPR, Swiss FADP): access, rectification, erasure, restriction of processing, data portability, objection to processing based on legitimate interests, withdrawal of consent at any time, and complaint to a supervisory authority, for example in the country where you live or work (in the UK, the Information Commissioner’s Office).
• United States (California CCPA as amended by the CPRA, and the comprehensive privacy laws of other states such as Virginia, Colorado, Connecticut, Texas and Oregon): to know and access, delete, correct and port personal information; to opt out of its sale or sharing, of targeted advertising and of profiling; to limit the use of sensitive personal information; to appeal a refusal; to use an authorised agent; and not to be discriminated against for using these rights. Notice for California residents: in the last 12 months the developer has not collected personal information through the app, other than e-mails you chose to send us. We have not sold or shared personal information, and we do not use sensitive personal information. Global Privacy Control signals are honoured where the law requires; today there is nothing to opt out of.
• Canada (PIPEDA and provincial laws, including Québec’s Law 25): access, correction and withdrawal of consent; complaints to the Office of the Privacy Commissioner of Canada or, in Québec, the Commission d’accès à l’information.
• Brazil (LGPD): confirmation of processing, access, correction, anonymisation, blocking or deletion, portability, information about sharing and revocation of consent; complaints to the ANPD.
• Japan (APPI): disclosure, correction, suspension of use or deletion; complaints to the Personal Information Protection Commission.
• South Korea (PIPA): access, correction, deletion, suspension of processing and withdrawal of consent; complaints to the Personal Information Protection Commission or the KISA privacy centre. The person responsible for personal information is the developer, reachable at [email protected].
• Australia and New Zealand (Privacy Act 1988, Privacy Act 2020): access and correction; complaints to the OAIC or the New Zealand Privacy Commissioner.
• Other countries (for example India’s DPDP Act, Singapore’s PDPA, South Africa’s POPIA or Türkiye’s KVKK): the rights your local law gives you. Write to us and we will respond in line with it.

How we respond. We answer within one month, or sooner or later where your local law sets another period (for example 45 days under the CCPA), and we may extend it where the law allows. We may ask for information to confirm that a request comes from you. Requests are free unless they are manifestly unfounded or excessive. If we cannot do what you ask, we explain why and how you can appeal or complain.

12International users

Molveth is available in many countries. The developer does not receive the data you keep in the app, so we do not transfer it anywhere.

If you e-mail us, your message is processed by our e-mail provider and may be stored on servers outside your country. Where the GDPR or UK GDPR applies to such a transfer, it relies on an adequacy decision, on standard contractual clauses offered by the provider, or on the transfer being necessary to answer your request.

This policy is written in English. If a translation is offered, the English version prevails unless your local law requires otherwise.

13Security

Molveth uses Android’s application sandbox for private working data. It does not add a password-protected vault or promise encryption beyond what your device provides. Archives and exported documents are ordinary files. Use a device screen lock, keep your device updated and choose trusted destinations.

No device or storage system is perfectly secure. Someone with access to an unlocked, compromised or rooted device, an exported archive or a shared file may read it. Avoid putting other people’s personal information in worksheet titles or notes, and do not send private files to support unless they are needed for your request.

14Ads, purchases and future versions

Today. The current version of Molveth is free of charge, shows no ads, has no in-app purchases or subscriptions, and contains no advertising, analytics or payment SDKs. This describes the app as it is now, not a promise about future versions. Future versions may introduce advertising, paid features, in-app purchases or subscriptions, or other optional services.

If ads are introduced. Ads would be supplied by a third-party ad network, for example Google AdMob. Ad networks typically process your device’s advertising ID, IP address, approximate location derived from the IP address, device and app information and your interactions with ads, in order to show ads, limit repetition, measure performance and prevent fraud, and, only where you allow it, to personalise ads. Ads would also require the app to connect to the internet, which the current version cannot do.

If purchases or subscriptions are introduced. They would be processed by Google Play’s billing system. Google handles your payment details under the Google Privacy Policy. We would receive only what is needed to deliver and verify a purchase, such as a purchase token, the product, its status, the country and the currency, never your full card or bank details.

Before any such change we will update this policy with a new effective date and version, describing what data is processed, by whom, why and how you can control it; update the Google Play Data safety section; mention the change in the release notes; ask for your consent where the law requires it (for example for personalised ads and non-essential access to your device in the EEA, the UK and Switzerland, through a consent tool that meets Google’s requirements); and offer the opt-outs the law requires (for example under US state privacy laws). The change applies only from the app version that introduces it. Data already stored in the app will not be used for advertising without telling you first and, where required, getting your consent. We will not knowingly show personalised ads to children (§15).

15Age limits

Molveth is a general chemistry study tool and is not directed to children under 13. A parent or guardian who believes a child has sent us personal information can contact support to request its deletion. We cannot inspect or remotely delete data that exists only on your device.

16Changes to this policy

We may update this policy when we change the app (including any change described in §14), when the services the app uses change, or when the law changes. The effective date and version at the top of this page show which version applies, and the version history (§17) summarises every change.

For a material change, for example new data leaving your device, ads or purchases, we update this page and the Google Play Data safety section before the app version with that change is published, describe it in the release notes, and ask for your consent in the app where the law requires it. Changes do not apply retroactively to data processed before them. Earlier versions are available on request from [email protected].

17Version history

18Contact

• Developer (controller): Zydeno, the developer of Molveth on Google Play
• E-mail for privacy questions and requests: [email protected]
• Website: zydeno.com

We aim to answer within 30 days. If you are not satisfied with our answer, you can contact your local data-protection authority.

See also the Terms of Use.