Privacy Policy

1Who we are

Chamferline is an offline 3D modeler for 3D printing for Android, developed by Zydeno. It lets you build parts from boxes, cylinders, text and templates, cut holes, type exact sizes, check a part for printing problems, fit parts together with clearances for your printer and material, open and repair STL, 3MF and OBJ files, and export your work. This policy explains what the app keeps on your phone, how files move in and out when you choose, and what happens if you contact us at [email protected].

Chamferline is an independent app. It is not affiliated with or endorsed by any 3D printer maker or software company.

2What this policy covers

This policy covers the Chamferline Android app. It does not cover your phone’s operating system, the browser, e-mail, file, cloud-storage, messaging and slicer apps you use to open, store or send files, or the web host that serves this page, whose own terms and privacy policies govern the data you give them.

The app works without an account and without 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 parts, models, imported files, part names, text you engrave, printer and material settings, clearance results, preferences, device identifiers or any other information. It has no account registration, no advertising SDK, no analytics SDK and no third-party crash reporter. It does not request internet, location, camera, microphone, contacts, phone, notification, photo-library or storage-wide access.

We do not receive, sell or share your in-app data, use it for advertising or train models on it. Chamferline never asks for your name or contact details.

4What is stored on your phone

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

• Parts: each part’s shapes, sizes, holes, text and parameters, the meshes needed to show and export it, the part’s name (which can be in any script) and the view you left it in.
• History and versions: the undo history and the saved versions of each part, so you can go back or restore a version as a copy.
• Imported geometry: when you open an STL, 3MF or OBJ file and keep it, the geometry is copied into a part in the app’s storage. The original file stays where it was.
• Printers and materials: the printer size, nozzle and material you choose or define, and an optional price per kilogram or pound that you type in.
• Clearance profile: the fit results you record for your printer and material, for example which test pin fitted.
• Settings: language, each unit choice, theme, haptics, sounds, grid and snap options, and your progress through the introduction.

All modeling, repair, checking and exporting run on your phone. Part names and other free text are not checked or analysed; do not enter information you would not want kept on the phone. This data is removed when you uninstall the app or clear its storage.

5No internet access from the app

The Android app does not declare the INTERNET permission. It has no backend, no external API requests, no automatic uploads, no remote downloads, no online model library and no cloud synchronisation. Fonts, sounds, templates, printer and material presets and help text are bundled in the app.

Links. When you open this policy, the Terms or the 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 Chamferline itself, and a support e-mail is sent only if you choose to send it.

6Files, export, sharing and import

Open and import. You can open an STL, 3MF or OBJ file from inside the app with Android’s file picker, or choose Chamferline in another app’s “Open with” or share menu. Android then gives the app read access to that one file only; no storage permission is needed. The app reads the file on the phone, checks it, repairs it where it can and adds it as a part. Files that are not valid are rejected.

Export and share. You can export a part or all parts as STL, 3MF or OBJ, and Export all creates one backup archive of every part and your clearance profile. A file is created only when you tap Export. It is written to the place you choose in Android’s file picker or handed to the app you choose in the share sheet. To hand a file to the share sheet the app may keep a temporary copy in its private storage, which is removed with the app’s storage. Exported files describe your geometry, names and units and contain no location or device identifier.

Your destination matters. A printer app, slicer, chat app, e-mail app, cloud drive or other recipient receives the file you choose to give it and keeps it under its own policy. Exported files are ordinary, unencrypted files. This is a transfer you start, not automatic synchronisation. Zydeno receives no copy unless you deliberately send one to support.

7Permissions and device access

Chamferline asks Android for no permission that needs your approval. The app declares only the ordinary vibration permission, which lets it give haptic feedback and which Android grants without a prompt. It does not request internet, location, camera, microphone, contacts, phone, notification, photo or media, storage-wide, all-files, Bluetooth, exact-alarm or Accessibility-service access, it runs no foreground service, and the advertising-ID permission is removed from the app.

Region and fonts. To choose sensible default units, number and date formats, the app reads your device’s region and language settings locally. To draw 3D text in Chinese, Japanese or Korean script on Android 10 and later, the app looks in the list of fonts installed on your phone for a suitable system font. Both are used on the device only and are not transmitted. You can change every unit and the language in Settings.

Other device features. Sounds play through your phone’s audio output and follow silent mode and your sound settings; the microphone is never used. Haptic feedback and sounds can be switched off in the app or in Android.

8Your controls, backups and deletion

You can delete parts and versions, change every setting, export your data, and use Settings, Your data, Delete all to remove all parts, versions, printers, clearance profile and settings after you confirm. Export first if you want to keep a copy.

Automatic Android cloud backup is turned off for the app. Depending on your device and Android version, a device-to-device transfer when you set up a new phone may still copy the app’s data; to move your work deliberately, use Export all and Import. If the phone is lost or the app’s storage is cleared without an export, the developer cannot restore your data.

Uninstalling Chamferline or clearing its storage in Android Settings removes its private data. Deleting items in the app does not delete files you exported or copies held by other apps or people; remove those separately.

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 process special categories of personal data; the models, part names, printer and fit settings you create stay on your phone and the developer receives none of them.

10How long information is kept

Your parts, versions, printer and material settings, clearance profile and preferences stay on your phone until you remove them, clear the app’s storage or uninstall the app. Deleting an item is not a guarantee of forensic erasure of every byte on the device. Files you saved or shared outside the app remain under your control, or the recipient’s, and may outlast uninstallation.

11Your privacy rights

Privacy laws in many countries give you rights over your personal data. Because Chamferline 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

Chamferline 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

Chamferline relies on Android’s application sandbox for its private data. It does not add a password-protected vault or promise encryption beyond what your device provides. Exported files are ordinary files, and the models in them may reveal what you design.

The app reads files you open with defensive checks and rejects files it cannot parse, but no software can promise that a file from an untrusted source is safe or will open. No device or storage system is perfectly secure. Someone with access to an unlocked, compromised or rooted phone, or to an exported file, may read it. Use a screen lock, keep your phone updated and share files only with people you trust.

14Ads, purchases and future versions

Today. The current version of Chamferline 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

Chamferline is a tool for makers and is intended for adults. It is not directed to children and is not designed to appeal to them. It does not collect personal information from anyone, so it holds no information about children. A parent or guardian who believes a child has sent us personal information, for example by e-mail, can contact support to request its deletion.

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 Chamferline 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.