Privacy Policy – PDF Hub
Last updated: 15 August 2026
Developer: elm-cr4
Application: PDF Hub
Package: com.elm_cr4.pdfhub
Contact: support.elmcr4@gmail.com
ENGLISH
1. Overview
PDF Hub is a local-first PDF viewer and document scanner provided by elm-cr4. No PDF Hub account is required, and elm-cr4 does not operate a backend that receives users’ documents. Documents selected, scanned, saved, or viewed in PDF Hub are handled locally except when a user deliberately shares a document with another app or service.
PDF Hub uses Google services for document scanning, advertising consent and privacy choices, advertising, and the optional Premium purchase. Those Google services may process limited technical, advertising, and purchase information as explained below. This policy distinguishes document contents, locally stored metadata, Google ML Kit technical information, Google Mobile Ads data, Google Play purchase data, and user-initiated sharing.
2. Files selected by the user
Users open PDFs through Android’s system file picker. PDF Hub receives access only to the files a user selects and may retain an Android read-access grant so the file can be reopened. PDF contents are rendered locally. PDF Hub does not upload selected PDFs to a server operated by elm-cr4.
Removing an entry from Recent removes the app’s history metadata; it does not delete the underlying PDF and may not immediately revoke Android’s retained file-access grant.
3. Information stored locally
PDF Hub may store selected document URI references, display names, file size and date metadata supplied by the document provider, Recent ordering and last-opened time, Favorite status, theme preference, a locally cached Premium-entitlement status, app-use count, and the last collapsible-ad request time. Temporary scan-saving state, such as a content URI, page count, or proposed file name, may also be retained while a save operation is being completed.
This information is stored in the app’s sandbox. PDF Hub does not place the contents of selected PDFs in its metadata store. Its settings data is excluded by the app’s Android backup and device-transfer rules. Google Play remains authoritative for Premium ownership; the local Premium cache supports offline continuity.
4. Document scanning and Google ML Kit
Document scanning uses Google ML Kit Document Scanner through Google Play services. Google Play services provides the scanner interface and Camera access; PDF Hub itself does not request the Android Camera permission. Users may also choose images through the scanner interface where that option is available.
According to Google, scanner input images and generated output contents are processed on the device and are not sent to Google servers by ML Kit Document Scanner. Google Play services may download scanner components, models, fixes, or compatibility information.
ML Kit may transmit technical information to Google, including device and app information, device or installation identifiers, performance metrics, API configuration, input and output sizes, feature versions and usage events, and error codes. Google states that it uses this information for diagnostics and usage analytics, encrypts it in transit using HTTPS, and does not transfer the listed ML Kit technical data to third parties. elm-cr4 does not receive scanned-page contents through ML Kit.
5. Advertising and Google AdMob
Eligible users of the free version may see advertisements on the Documents and Tools screens. Settings and the PDF Viewer are designed without advertisements. A controlled collapsible banner may appear on Documents. Purchasing PDF Hub Premium removes all advertisements.
PDF Hub uses Google Mobile Ads (AdMob). Google’s disclosure for Google Mobile Ads SDK version 25.4.0 states that the SDK automatically collects and shares, when applicable:
• IP address, which may be used to estimate general or approximate location;
• user product interactions, including app launches, taps, video views, and related interaction information;
• diagnostic and performance information, including app launch time, hang rate, energy usage, and SDK or app performance information; and
• device and account identifiers, including the Android Advertising ID, App Set ID, and, where applicable, other identifiers related to signed-in accounts on the device.
Google states that these data categories are used for advertising or marketing, analytics, and fraud prevention, security, and compliance, and that Mobile Ads data is encrypted in transit using TLS. Depending on region, consent and privacy choices, platform controls, and available ad-serving modes, ads may be personalized, non-personalized, or limited. Advertising-ID transmission may be affected by Android controls and limited-ad behavior.
PDF Hub does not send users’ PDF contents to AdMob and does not directly receive all raw data processed by the Mobile Ads SDK. Advertising SDK behavior is governed by applicable Google terms and privacy practices.
6. Consent and privacy choices
PDF Hub uses Google’s User Messaging Platform (UMP). In applicable regions, Google may present a consent or privacy message. PDF Hub asks UMP to refresh consent information when the app starts and relies on UMP to determine whether ad requests are permitted.
When Google requires it, a Privacy choices entry is available in Settings so users can reopen Google’s privacy form. Choices may affect ad personalization and Google SDK processing. Depending on the choice and applicable law, Google may serve personalized, non-personalized, or limited ads, or may prevent an ad request. Premium removes ad display and ad requests, but Privacy choices may remain available where Google requires them.
7. PDF Hub Premium and Google Play Billing
PDF Hub offers premium_lifetime, a permanent, non-consumable one-time purchase. It is not a subscription. Premium permanently removes advertisements for the purchasing Google Play account while Google Play reports the entitlement as owned.
Google Play processes the payment and may process account, payment, transaction, device, and purchase information under Google’s terms and privacy practices. PDF Hub receives purchase state, product identity, purchase-token and entitlement information needed to complete the purchase, acknowledge it, restore ownership, and activate Premium. PDF Hub does not receive or store card numbers or bank-account information and does not operate a billing backend.
PDF Hub stores only a local last-confirmed Premium status for offline continuity. The app queries Google Play to restore and reconcile ownership; Google Play’s current successful result remains authoritative.
8. Saving and sharing documents
Scanned PDFs are saved only after the user chooses a destination through Android’s system interface. Saved files remain with the selected device location or document provider. PDF Hub does not automatically upload them to elm-cr4.
Sharing occurs only when a user selects Share and chooses a receiving app or service through Android’s system share interface. The receiving party’s privacy practices then apply. elm-cr4 does not automatically receive a shared document.
9. Network access
PDF viewing and local document metadata do not require an elm-cr4 server. Network access may nevertheless be used by Google services to obtain UMP consent and privacy messages, request and deliver advertisements, process and reconcile Google Play purchases, download ML Kit scanner components, and transmit the limited technical information described in this policy.
Ad or network failures do not prevent users from using PDF Hub’s local document features. Data transferred to Google is handled under applicable Google terms and privacy practices.
10. Sharing and sale of information
elm-cr4 does not sell users’ PDF documents or local document metadata. elm-cr4 does not operate a backend to receive those documents or metadata.
Google Mobile Ads automatically collects and shares applicable advertising data as described in section 5. Google ML Kit processes the technical data described in section 4 and states that it does not transfer that listed technical data to third parties. Google Play processes purchase information as described in section 7. A user may independently direct a document to another app or service by using Share; that user-initiated transfer is controlled by the user.
11. Data retention and deletion
Recent, Favorite, preferences, ad-pacing values, and the cached Premium status remain locally until removed by an available app control, app data is cleared, or PDF Hub is uninstalled. Clearing Recent preserves Favorites. Removing a Recent entry does not delete the actual PDF. Android may retain a selected file-access grant until Android or the document provider revokes it, app data is cleared, or the app is uninstalled.
PDFs saved to a selected location remain there until the user deletes them through the applicable file manager or provider. Users can remove Recent entries, clear Recent, remove Favorite status, delete saved files, clear PDF Hub’s app data in Android Settings, or uninstall PDF Hub. There is no PDF Hub account to delete and no elm-cr4 server-side document record.
Google controls retention and deletion of Mobile Ads, UMP, ML Kit technical, and Google Play purchase information under Google’s applicable terms, controls, and privacy practices. elm-cr4 cannot inspect or remotely delete Google-held SDK data or files stored locally on a user’s device.
12. Security
PDF Hub uses Android app sandboxing, the Storage Access Framework, scoped URI access, user-selected save destinations, and Google Play Billing. It does not request broad storage access. Google states that the Mobile Ads data described above is encrypted in transit using TLS and that the listed ML Kit technical transmissions are encrypted in transit using HTTPS.
No system can guarantee absolute security. Device security, document providers, Google services, and apps selected for sharing have their own security practices.
13. Children
PDF Hub is a general-purpose utility and is not specifically directed at children. The app does not knowingly operate an account or document backend for children. Advertising, audience settings, store presentation, and Google SDK configuration must continue to comply with the age and regional requirements applicable to the released app.
14. Changes to this policy
This policy may be updated when PDF Hub’s features, SDKs, legal requirements, or data practices change. The “Last updated” date will be changed when a revised policy takes effect.
15. Contact
For privacy questions about PDF Hub, contact elm-cr4 at support.elmcr4@gmail.com.