HashPhotos does not process anything on the server or transmit any user photo/video data or related data to the server.
To analyze errors and user usage patterns, only feature usage logs and error information are sent to Google Analytics and Firebase Crashlytics in a way that does not identify users.

If you lose your passcode, recovery or reset is not possible because HashPhotos is not a membership-based service.

The system library is a library managed by the iOS Photos app, and HashPhotos also manages albums and photos in the system library through the functions provided by iOS.
The local library is a library managed by HashPhotos, and the photos in this library are stored within the HashPhotos app and cannot be accessed by external apps.
If you delete the HashPhotos app, all photos in your local library will also be deleted.

Keywords, memos, and event data added in the app are stored in the database managed by the HashPhotos app.
Photos and video files in the Local Library are stored within the HashPhotos app sandbox.
All of these are stored only on the user’s device, and they will be deleted if the app is uninstalled.

Location information, date/time information, and titles added to photos in the System Library are stored in the database managed by iOS and will remain even if the HashPhotos app is deleted.
(Keywords, memos, and events are managed by the HashPhotos app and will be deleted along with the app.)

If you're using iCloud Photos to sync your photos, you can sync keywords manually.
Please check out guide: Manual Sync Guide
Check out [What is "System Keywords" option in the settings.] too.

HashPhotos manages own database for keywords and writes these keywords into IPTC when sharing, transferring or exporting photos from HashPhotos.
(Including/excluding keywords when sharing or transferring can be set in HashPhotos Settings > Privacy)
Writing keywords into IPTC directly whenever adding or editing keywords is very inefficient. Also there are limitations because of the iOS policy.
Check out [What is "System Keywords" option in the settings.] too.

iOS has an internal feature to manage keywords.
This feature also allows you to search by keyword in the Photos app and sync across devices if you use iCloud Photos.
HashPhotos used this feature to implement the keyword feature, but unfortunately Apple restricts 3rd party apps like HashPhotos from using this feature and upload to the App Store.
HashPhotos will support this feature as soon as Apple allows it.

Syncing albums and photos in the local library to multiple devices is not supported.

You can install and use the iPad version on Mac computers using M series chips.
However, since it is not yet a version that properly supports macOS, some features may not operate smoothly.
We are currently focusing on the iPhone and iPad versions, but we plan to pay more attention to the macOS version in the future.

iOS is preventing third-party apps from accessing the "Recently Deleted Items" album.

A zip file created using the "Backup" function can only be used when restoring with the restore function. The zip file contains data structured for HashPhotos use and is not intended for users to extract and use directly.
A password is set to prevent users from decompressing the file.
If you want to back up your albums and photos, please use the Export Album feature.

When searching for duplicate photos, scanning all images would take a significant amount of time, so HashPhotos groups images by their creation time and then searches for duplicates within those groups. Therefore, even if two images are identical, they may not be detected as duplicates if their creation times are significantly different.
To address this, HashPhotos includes an additional step to compare images with the same resolution. However, photos with common resolutions are often excluded to avoid comparing too many images at once.

Photos in the Local Library are stored in the HashPhotos app's sandbox storage, which is inaccessible to other apps. Because they are stored in the app's sandbox, if the app is deleted, all photos in the Local Library will be deleted as well and cannot be recovered. (It is highly recommended to back up photos stored in the Local Library elsewhere.)

These photos are only stored on the device where the app is installed and are not uploaded to any server or cloud. Synchronization with other devices is not supported for the Local Library.

When switching to a new device, photos in the Local Library can be preserved if you use the iPhone's full backup/restore feature or the data transfer function supported by iOS when setting up a new phone. These methods restore all app data, including photos in the Local Library, to the new device exactly as they were on the old device.

iOS doesn't replace the original when you edit a photo; it has two versions: the original and the modified version. So it takes up almost twice as much storage space.

When you edit a photo in iOS, it saves both the original and the edited version, which takes up more storage space. Additionally, for operations that only require metadata changes, iOS constraints necessitate saving not just the modified metadata but the entire image again.

While the differences might be imperceptible in most cases, formats like JPEG that use compression could potentially experience slight changes if re-compressed. To prevent this and to avoid duplicating storage, HashPhotos saves a new image with only the metadata changes and deletes the original.

This approach ensures that your edits are applied efficiently without unnecessarily increasing storage usage or risking unintended changes to image quality.

Unfortunately, iOS restricts access to the People album for third-party apps like HashPhotos. Due to this limitation, we are unable to provide this feature in our app.