1. Who we are

Waifu Deck is a free, open-source (AGPL-3.0) Android app for collecting anime artwork, developed by an individual developer (fancydirty). There is no company, no user database, and no backend service behind the app. Privacy questions: privacy@waifudeck.app.

2. What the app stores — and where

Everything the app knows is stored on your device, in the app's private storage:

• the images you keep, their source links and tags, and the identities of images you have already seen or dismissed;
• your settings (for example content-rating preferences, enabled sources, language);
• optional API keys you enter for an art source, and optional credentials or tokens for a cloud library you connect (kept in Android's secure storage).

Uninstalling the app deletes all of this. We never see any of it.

3. Art sources (third parties)

The app fetches artwork directly from your device to the public art sources you enable — currently Danbooru, e621, e926, Gelbooru, Konachan, Nekos API, Rule34, Safebooru, waifu.im and yande.re. Those services receive your device's network requests (including its IP address) under their own privacy policies and terms; the app adds nothing to those requests beyond what is needed to fetch images. Requests go directly to them, never through us.

4. Optional cloud library (storage you own)

You may connect the app to storage that you control so your collection is backed up and can be synced between your devices. Supported or planned locations: an S3-compatible bucket (for example Cloudflare R2, MinIO, Wasabi), Google Drive, or a WebDAV server (including self-hosted OpenList/AList, Nextcloud, NAS devices and providers that offer WebDAV).

• What is uploaded: your kept images (original, preview and thumbnail files), their metadata (source link, tags, size) and the state of your library.
• Encryption: the data is encrypted on your device (AES-GCM) with keys derived from a password only you know before it is uploaded. Encryption is on by default. We do not have the password and cannot recover it for you; if you lose it, encrypted data cannot be read by anyone.
• Credentials and tokens for your storage are stored only on your device and are sent only to the storage provider you configured. Disconnecting the cloud library deletes them from the device.
• The storage provider (Google, Cloudflare, your WebDAV host, and so on) processes your data under its own terms and privacy policy.

4a. Google Drive

When you connect Google Drive, the app requests the https://www.googleapis.com/auth/drive.file scope. This scope only lets Waifu Deck see, create and manage the files and the "Waifu Deck" folder that the app itself creates in your Drive. It cannot read, list or change any other file in your Google Drive.

• Google user data received through this scope (the contents and metadata of the app's own folder, and the OAuth tokens) is used solely to store and sync your own collection for you.
• It is not shared with anyone, not sold, not used for advertising or for building profiles, and never transferred to any server operated by us — the app has none. No human reads it, except if you explicitly ask for support and share it yourself, or where required by law.
• OAuth tokens are stored in your device's secure storage and are deleted when you disconnect Google Drive in the app. You can also revoke the app's access at any time at myaccount.google.com/permissions.
• To delete the synced data, delete the "Waifu Deck" folder in your Google Drive.

Waifu Deck's use and transfer to any other app of information received from Google APIs will adhere to the Google API Services User Data Policy, including the Limited Use requirements.

5. Permissions the app asks for

• Internet — to fetch artwork from the sources you enable and, if configured, to talk to your own cloud storage.
• Photos / media access — only when you export an image to your gallery or import a backup file.
• Notifications — to show progress while a cloud sync continues in the background.

The app never asks for your camera, microphone, contacts or location.

6. Children

Waifu Deck is not intended for children. Adult content is off by default and can only be enabled after an explicit 18+ confirmation.

7. This website

waifudeck.app is a static site. It sets no cookies and runs no analytics or tracking scripts. It is served by Cloudflare, which as our hosting provider may process connection data such as IP addresses to deliver the site and protect it from abuse, under Cloudflare's privacy policy.

8. Changes

If the app's data handling changes (for example a new sync location or a new permission), this page will be updated and the date at the top will change. Because the source code is public, the actual behaviour can always be verified.