Privacy Policy

Duo Viewer is an iPhone app provided by Liangjun Song for browsing websites and viewing files side by side. This policy explains how the app handles information and how to contact its publisher.

Information stored on your device

Duo Viewer does not require an app account. The app stores the following information locally to provide its features:

• Files: copies of documents, images, audio, and video you choose to import, together with filenames and reading or playback positions.
• Bookmarks: website addresses and names you save.
• Recent addresses: up to ten recently entered website addresses. Searches generated from text entered in the address bar are not added to this list.
• Saved sessions: when Resume Previous Session is enabled, information needed to restore your panes, including website addresses, open files, and layout.
• Preferences and website data: app settings and data stored by websites through Apple's WebKit, including cookies, caches, and local storage.

The app does not upload your file library, bookmarks, recent addresses, or saved sessions to a server operated by the publisher. It does not include advertising, analytics, or third-party crash-reporting SDKs. The publisher does not sell your personal information or use the app to track you across other companies' apps and websites.

Local app data may be included in device backups according to your Apple settings. Importing a file from a cloud provider uses that provider's service; the imported copy is stored in Duo Viewer. The app does not provide its own cloud synchronization.

Browsing, searches, and third-party websites

When you open a website, Duo Viewer connects to that website using WebKit. The website and its service providers may receive your IP address, browser information, requested addresses, cookies, and information you submit, such as login details or uploaded files. Their privacy policies govern that processing. Duo Viewer is not an anonymous browsing service.

Text entered in the address bar that is treated as a search is sent to Google as a search query. Although generated searches are not added to Recent Addresses, search pages may remain in browser navigation history, website storage, or a saved session.

The app's home page and its icons are bundled with the app. Opening a shortcut connects to the selected third-party website.

Purchases

Duo Viewer Pro is a one-time in-app purchase processed by Apple. The app uses Apple's StoreKit to check purchase status, unlock features, and restore purchases. The publisher does not receive your payment card details through the app. Apple handles payment and transaction information under its privacy policy.

Your controls and data retention

Locally saved information is retained until you remove it or the app updates it as part of normal use. You can:

• Delete imported files from the file list when they are not open. This also removes their saved reading positions; it does not delete the original file from its source.
• Delete individual bookmarks from the bookmarks list.
• Use Settings → Clear Recent Addresses to remove the recent-address list. This does not delete bookmarks or all browser data.
• Use Settings → Clear All Cookies to delete website cookies. This may sign you out, but it does not clear all website caches or local storage.
• Turn off Resume Previous Session to delete the saved session, or use Reset Workspace to delete it and return the panes to the home page. Reset Workspace keeps files, bookmarks, and file reading positions.
• Delete the app, rather than offload it, to remove its local app data from the device. Backups, original cloud files, Apple purchase records, and information held by websites are managed separately by their respective providers.

The publisher cannot access or remotely delete your local file library or browsing data. Contact the relevant website or service provider about information you have submitted to it.

Privacy questions and support

Contact Liangjun Song at hello.duoviewer@gmail.com with privacy questions or requests. If you email, your email address and message will be processed to respond and handle your request. Do not include sensitive files or browsing information unless necessary.

This policy website

This page is hosted on Cloudflare Pages. Visiting it sends technical request information, such as your IP address and browser information, to Cloudflare to deliver and protect the page. See Cloudflare's privacy policy. This page includes no analytics scripts, advertising, or embedded third-party content.

Changes to this policy

This policy may be updated as the app or its practices change. The current version will be available on this page with an updated date.