Privacy Policy — PDF Converter
Effective: November 10, 2026 · 한국어
Owlmakers ("the Developer") takes the privacy of people who use PDF Converter ("the App", store title: PDF to Image Converter - Auto Crop Margins) seriously. This policy explains how the App handles information.
Summary
· The PDFs and photos you choose are processed only on your device. File contents, file names and photos are never sent to the Developer's servers or to third parties.
· The App has no accounts, sign-in or registration.
· The App does not request full storage access, camera, location, microphone or contacts permissions. It reads only the files you pick yourself in the system file picker or photo picker.
· The App does use ads (Unity LevelPlay and Google AdMob), notifications (come-back reminders and news push), anonymous usage statistics (Google Analytics for Firebase) and the Developer's anonymous usage counts (Owlmakers server). File contents, file names, page contents and exact page counts are not part of any of these.
1. PDFs and photos — they never leave your device
- The App reads only PDFs you choose in the system file picker, photos you choose in the system photo picker, or files another app sends to it with Share / Open with. Conversion (PDF to images, images to PDF) and automatic margin cropping all happen on your device.
- The contents, names and addresses (URIs) of your PDFs and photos are not sent to the Developer's servers or to any third party. The part of the App that processes files makes no network connections.
- Your original files are never modified or deleted. Results are saved as new files in your photo gallery (the
Pictures/PDF변환 folder), your Downloads folder, or a location you choose.
- Temporary files for previews and for ZIP sharing are created in the App's cache folder, on your device only.
- Photos, file names, file addresses and page contents are never included in ad requests, usage statistics or usage counts.
2. Information stored on your device
The following is stored only on your device and is not sent to the Developer.
| Item | Contents |
|---|
| Settings | Conversion defaults (resolution, output format, crop mode, etc.), theme, display language, whether the first-run guide was seen, and ad display counts and the last display time (to limit interstitial ad frequency) |
| Job queue and history | Job names (the original file name), source file addresses (URIs), selected page numbers and manually set crop-area coordinates, processing status, and where results were saved. Stored so work can resume if the App is interrupted. |
| Pending usage counts | If the anonymous usage counts in section 4 cannot be sent, event codes are kept briefly on the device to be re-sent (up to 7 days and 500 events; the oldest are discarded first). They contain no file names or paths. |
| Backup file | A pdfconverter_backup*.json file containing the settings and job history above. It is written to your Downloads folder whenever the data changes, and "Back up to file now" in Settings creates a dated copy. It may contain original file names and file addresses but not the PDFs or photos themselves; it stays on your device and is not sent to the Developer. |
3. Ads — Unity LevelPlay and Google AdMob
The App is free and shows ads (a banner at the top of the screen, banner-style ads in the exit dialog and on the home, jobs, history, progress and result screens, and interstitial ads after a conversion finishes, after you return from the share sheet, and similar moments). Ads are loaded through the ad mediation service Unity LevelPlay (ironSource, Unity Technologies), and ad networks connected to it (currently Unity Ads and others) fill them. The App also includes the Google AdMob ad SDK. No interrupting ads are shown while you set options, adjust crops or while a conversion is running.
- These ad SDKs may collect your advertising ID (AAID), IP address, device information, ad interactions and information about the apps installed on your device to serve ads and prevent invalid impressions, and the advertising ID and installed-app information may be passed to ad mediation and ad network providers (Unity Technologies, Google and others). The app itself does not read the list of apps installed on your device.
- This follows each provider's own policies. The developer does not separately collect or keep this information. PDFs, photos and file names are never passed to ads.
- Google's advertising data practices: https://policies.google.com/technologies/ads
- Unity privacy policy: https://unity.com/legal/privacy-policy
- Ad personalization: reset or delete your advertising ID, or turn off personalized ads, in device Settings → Google → Ads, and reopen your consent choice from "Ad privacy settings" in the app settings.
- Users in the European Economic Area and the UK see a consent (UMP) dialog on first launch. The ad SDKs start only after that step is complete, and the consent result is also passed to the ad mediation service.
4. Usage statistics and usage counts
4-1. Google Analytics for Firebase
To improve the App and keep it reliable, it collects anonymous usage statistics with Google Analytics for Firebase.
- What is collected — which screens were opened (home, jobs, history, options, crop adjustment, progress, result, settings, etc.), which buttons and switches were used (the item's name, on/off, or a choice number such as which tab), the outcome of conversion jobs (success, failure or cancel, and a failure category such as corrupt file, password-protected, out of memory, storage, read error, unsupported format), the direction (PDF to images or images to PDF), a page-count range (1-10, 11-100, 100+), the resolution (150/300/600 dpi) and whether cropping was used. Also a randomly assigned app instance ID per installation and information Google Analytics collects automatically (sessions, approximate region inferred from IP address, device and app version, advertising ID, etc.).
- What is not collected — PDFs, photos, file names, paths or file addresses, page contents, exact page counts, or personally identifying information such as name, email or phone number.
- Who processes it — Google collects and processes the data; the Developer sees only aggregated statistics in which no individual is identified. Google's privacy policy: https://policies.google.com/privacy
4-2. Owlmakers usage counts
To check that the App is working normally, it sends anonymous usage counts to the Developer's server (api.owlmakers.com, HTTPS). This is turned on only in the released (production) version.
Installation identifier — A random value generated once on first launch after installation and stored on the device. It is used only to count the same installation across days and is not linked to your name, account or any hardware identifier. It is removed when you uninstall the app or clear its data; where device auto-backup is enabled it may be restored when you reinstall.
- What is sent: app name, version and display language; the same kinds of screen navigation, button use and job-outcome codes as in 4-1; a signal that the App is in use; and a random value generated on each launch (it is not stored, so it does not identify you or your device).
- The server records only the country, region and city names derived from the connection route. It does not store your IP address, and the App neither sends nor receives location coordinates.
- Data is kept for one year and then deleted. It is not provided to third parties.
5. Notifications and push (Firebase Cloud Messaging)
The app can show two kinds of notifications.
- Come-back reminders — 3 and 7 days after you last opened the app, it shows a reminder such as "Try opening the app." Scheduling and showing them happen entirely on your device (the RECEIVE_BOOT_COMPLETED permission is used to restore the schedule after the device restarts), and nothing is sent to the developer's server.
- News notifications (push) — to receive app news sent by the developer, the app uses Google's Firebase Cloud Messaging (FCM). When the app starts, FCM creates an identifier for this installation (an FCM registration token and a Firebase installation ID), and the app asks Google FCM to subscribe it to two topics: the app name and your display language. Google processes the identifier and topics; the app does not send or store the token on the developer's server. User state such as location or saved information is never used as a topic.
Notification permission (Android 13 and above) — the system permission dialog is shown when you tap the in-app notice bar or the notification item in Settings, and once from the second launch after you have used the app. You can use every feature without allowing it (if you do not, the FCM identifier and subscriptions may still be created but no notification is shown). You can turn notifications off at any time in device Settings → Apps → Notifications.
6. Developer servers
The App has no accounts and does not send PDFs, photos or file names to the Developer's servers. The only thing that goes to the Developer's server is the anonymous usage counts in section 4-2.
7. Permissions the App requests
The App does not request permissions for full storage reading, photos and videos, camera, location, microphone, contacts or accounts. PDFs are read from the system file picker and photos from the system photo picker (Android 13+) or file picker (Android 12 and below), and only what you choose. On Android 9 and below only, it uses the storage write permission to save results to the photo gallery.
Internet access, network state, advertising ID access, keeping the device awake (WAKE_LOCK), and background services (FOREGROUND_SERVICE) are permissions declared by the ads and Firebase components. Showing notifications (POST_NOTIFICATIONS) and restoring the reminder schedule after the device restarts (RECEIVE_BOOT_COMPLETED) are for the notifications in section 5, and the notification permission dialog is shown only at the times described there. None of these permissions lets the App read your PDFs or photos.
8. App updates
Update prompts use Google Play's in-app update feature. The Developer receives no information about you in this process.
9. Children
The App is not directed to children under 14 (under 13 in some regions) and does not knowingly collect children's personal information.
10. Your rights and how to delete data
The Developer holds no personally identifying information (the anonymous usage counts are described in 4-2). You can delete information on your device at any time:
- Device Settings: App info → Storage → Clear data, or uninstall the App (this removes settings, job history and pending usage counts)
- Backup file (
pdfconverter_backup*.json): delete it from your Downloads folder with a file manager (it may remain after you uninstall the App)
- Conversion results: delete them from the
PDF변환 album in your gallery, from Downloads, or from the location you chose
- Advertising ID: reset or delete it in Settings → Google → Ads
11. Contact
12. Changes
If this policy changes, we will announce it on this page.