[Feature] Deletion Smart Sync From Native Photo App

[anikhossain285]

I have searched the existing feature requests, both open and closed, to make sure this is not a duplicate request.

• Yes

The feature

Problem
Immich currently operates as a strict one-way backup tool (mobile to server). While this ensures server data is never accidentally deleted by local device changes, it creates a maintenance challenge over time:

• Deleting photos in the native iOS/Android Photos app leaves them untouched on the server.
• Over time, the server accumulates a large backlog of unwanted photos ("junk" or duplicates cleaned up on the phone).
• Reviewing and sorting an entire server library manually on the web UI to find these items is cumbersome because there is no automated way to highlight what has already been discarded locally.

Proposed Solution

• Introduce an optional setting or workflow that leverages the existing mobile backup scan to flag assets that exist on the server but are no longer present on the mobile device's storage.
• Comparison During Backup: When the mobile app runs a backup scan (either on-app open or via scheduled background sync), it compares the list of uploaded asset IDs/hashes against the current state of the local device library.
• Identification & Tagging: Along with identifying new assets to upload, the app identifies missing assets (those present on the server but deleted locally).

Server-Side Action (Configurable):

Automatically apply a system tag (e.g., missing-on-device) to those assets, or route them into a dynamic system album (e.g., "Review Local Deletions").

Web UI Management:

Users can filter their library or open this specific album directly from the web browser.

Provide a clear interface to bulk-select these items and choose whether to Delete from Server or Keep in Server.

This approach preserves the core philosophy of a safe, one-way backup (preventing automatic data loss), but introduces a "smart sync" flexibility layer for users who want assistance culling their server archives based on what they've already decided to clean up on their primary devices. This would be beneficial for not-too-tech-savvy family members and those not habituated to deleting using the Immich app. The native app has more functions to filter and find photos and mass-delete compared to the Immich app running on a low-end config without ML.

Platform

• Server
• Web
• Mobile

[bo0tzz]

#4341