MOBILUCK · Privacy Policy

PDF Reader – Office Editor
keeps your documents on your device.

This policy explains, in plain language, what the app does with your files and data — and, just as importantly, what it never does.

App: PDF Reader – Office Editor (Mobiluck Reader) Developer: MOBILUCK CO., LTD Effective date: 6 September 2026

At a glance

1. Who we are

PDF Reader – Office Editor (also known as Mobiluck Reader) is developed and published by MOBILUCK CO., LTD ("MOBILUCK", "we", "us"), a software company registered in Vietnam. We build the app; we do not build a business on your data.

This policy applies to the Android application distributed on Google Play under the package name published by MOBILUCK, and to the single conversion service described in Section 5. It does not cover third-party apps you may open documents with, or websites you visit through links inside your documents.

2. What the app does with your files

The app is an offline document reader and editor for PDF, DOCX, XLSX, PPTX, EPUB, and TXT files. All reading, searching, highlighting, signing, form filling, page organising, content editing, and paper scanning happen locally on your device. Your documents are processed by the app on your phone, not on our servers.

Listing documents on your device

When you allow file access, the app lists compatible documents by querying the Android system media store. This listing reads only file names, sizes, locations, and dates. The app does not open or read the contents of any file until you tap to open it yourself.

Editing never touches your originals

Every modifying action — signing, filling a form, editing content, combining or reorganising pages, repairing a damaged file — produces a new file. Your original document is never overwritten by any flow in the app.

3. What we never collect

The app has no user accounts. Whatever else this policy says — including the section on ads — none of the following ever leaves your device:

Document content leaves your device in two flows only, each one described below and each one asking you first: file conversion (Section 5) and the AI assistant (Section 6).

Simple test: in airplane mode, everything except those two flows works exactly the same. That is by design, and it is the promise we hold ourselves to.

4. Data stored only on your device

To make the app useful, some information is saved locally in the app's private storage on your phone. None of it is transmitted to us:

DataPurposeWhere it lives
Reading history and positionsThe "Continue reading" list and returning you to the page you leftApp's private database on your device
Highlights, notes, and bookmarksYour annotations on documentsApp's private database on your device
Your drawn signatureReusing your signature when signing PDFsStored encrypted on your device only
Remembered document passwords (optional)Reopening a protected file without retyping the password, only if you switch this on per fileEncrypted with the Android Keystore; the app keeps only the encrypted form and the key never leaves the device's secure hardware
App preferencesInterface language, display settings, dismissed tipsApp's private storage on your device

Uninstalling the app deletes all of this data. Document passwords are used solely to decrypt files on your device and are never transmitted anywhere.

5. Converting a file on our server

Two things need a server, because they cannot be done on a phone:

Both use the same MOBILUCK conversion service, and both work like this:

6. The AI assistant

The AI assistant can summarise a document or answer a question about it. It is the second and last flow in which document content leaves your device, it runs only when you tap it, and the panel says so on screen every time you open it.

What is sent

Where it goes, and how long it stays

The text travels over TLS to a MOBILUCK service on Google Cloud, which passes it to our model provider, Groq, running the open-weights model openai/gpt-oss-120b. The request is marked “do not store”, so neither we nor the provider keep the text after the answer is produced. We write no document text to any log or database: our logs hold counts and timings only. No person reads your questions or your documents.

Answers can be wrong

Every answer carries citations back to the page it came from, so you can check it. Please do check anything that matters.

Daily limits

Free use is limited per day. The counter lives on your device; the server keeps a matching count against the Play Integrity identity of your installation, which tells us nothing about who you are.

7. Usage measurement and crash reports

To know which parts of the app people actually use and which ones break, the app sends anonymous measurements through Google Firebase Analytics and crash reports through Firebase Crashlytics. This is on by default and there is a switch in Settings to turn it off; turning it off stops collection immediately.

What a measurement event can contain — and why it cannot contain more

The app can only send events from a fixed list written into its source code, and those events accept only pre-defined choices and numbers. There is no way for the app to attach a piece of free text to an event, which is why no file name, no document content, no search term and no AI question can ever appear in one. Counts are rounded into ranges (1, a few, tens, hundreds, thousands) so that an unusual number cannot single anyone out.

In practice an event says things like: a document was opened, and it was a PDF of a few hundred pages; a conversion succeeded; an export failed because the daily limit was reached; the Pro sheet was shown; the rating prompt was shown.

What Firebase adds by itself

Firebase attaches a randomly generated app-instance identifier, your device model, operating-system version, app version, country-level location derived from the IP address, and coarse timing. Crashlytics reports contain the crash stack trace, the device model, the OS and app version, and a random installation identifier — never document content.

Google processes this data as our processor; see Firebase’s privacy documentation. Turning the switch off in Settings stops both Analytics and Crashlytics.

7a. Ads

From version 1.0.5 onwards, in some countries the app shows ads supplied by Google AdMob. Earlier versions contain no advertising code at all. Which countries is a setting we change from our side, so an app that shows no ads today may show them tomorrow, or stop, without an update.

Where they appear — and where they never do

There are exactly three places: a strip above the tab bar on the library screen, a full-screen ad after you close a document you spent at least twenty seconds with, and a full-screen ad when the app returns to the foreground, at most once every four hours.

There are no ads while you are reading a document, no ads in the notebook, and no ad when you open a document. Mobiluck Pro removes all of them.

What the ad SDK is given

The ad slot, and nothing about your content. Everything listed in Section 3 stays out of it: no file names, no document text, no notes, no search terms, no AI questions. AdMob receives what any app's ad request carries — your device model, operating-system version, coarse IP-derived location, and the Android advertising identifier.

That advertising identifier is the one thing this app did not send before it had ads, and it is why the Google Play data-safety label now lists Device or other IDs. You can reset or delete it at any time in your phone's Settings → Privacy → Ads.

If you turn the measurement switch off (Section 7), the app also asks AdMob for non-personalised ads — the same switch, honoured in both places. You will still see ads; they will just not be chosen from a profile.

8. Subscriptions and payments

The app is free to use. Reading, searching, signing, editing, scanning and everything else that runs on your device is free and unlimited, and always will be. An optional subscription, Mobiluck Pro, removes the daily limits on the two server features (Sections 5 and 6) and removes ads entirely (Section 7a).

9. Reporting a file that will not open

If a file fails to open, the app may offer to send a report so we can fix the reader. It is strictly opt-in and contains technical facts only: the file format, the file size, and an internal error code. It never contains the file name, the file content, or anything identifying you.

The report goes out through the Android share sheet, so you can read exactly what would be sent — or simply not send it.

10. App permissions and why we ask

PermissionWhy the app requests it
All files access (MANAGE_EXTERNAL_STORAGE)To list compatible documents already on your device in the Documents tab. Listing reads names and sizes only (Section 2). This permission is optional: you can decline it and open files one at a time through the system file picker instead.
CameraOnly for the Scan feature, to photograph paper documents you choose to scan into a PDF. The camera is never accessed outside an active scan you started. Scanned images are saved on your device.
InternetUsed for: file conversion (Section 5, with your consent each time), the AI assistant (Section 6, only when you tap it), anonymous measurement and crash reports (Section 7, switchable off), subscription checks with Google Play (Section 8), and the first-run download of the on-device scanner module. Reading, editing, signing and searching never use the network.

11. Security

Because your data stays on your device, your device's own protections (screen lock, encryption) are the primary safeguard — and the app adds its own: signatures and remembered passwords are stored encrypted using the Android Keystore, the app's database is kept in private app storage inaccessible to other apps, and the single network flow in Section 5 uses TLS encryption in transit. No method of transmission or storage is 100% secure, but minimising what exists in the first place is the strongest protection we know: data that is never collected cannot be leaked.

12. Children’s privacy

The app is a general-purpose document reader, is not directed at children, and collects no personal data from anyone — including children. Because there are no accounts and no data collection, we do not knowingly process any child's personal information. If you believe a child has somehow provided personal data to us (for example, by email), contact us and we will delete it.

13. Your choices and rights

Since we hold no personal data about you on our servers, there is typically nothing for us to export, correct, or erase on request — but if you believe we hold any data related to you (for example, from an email you sent us), you may exercise your applicable rights under laws such as the GDPR or Vietnam's Decree on Personal Data Protection by contacting us (Section 15).

14. Changes to this policy

If we change how the app handles data — for example, if the AI assistant ever changed provider — we will update this page, revise the effective date at the top, and, for any change that would allow data to leave your device, ask for your consent inside the app before the change applies to you.

15. Contact us

Questions about this policy or the app's data practices:

MOBILUCK CO., LTD (CÔNG TY TNHH MOBILUCK)
Hanoi, Vietnam
Email: congvt@mobiluck.vn · vutricongbka@gmail.com
Website: https://mobiluck.vn · https://code247.ai