Deleting duplicates on iPhone: what DeDup 1.0.1 does, step by step

On iPhone, the result screens in DeDup 1.0.1 don't have a Delete button. They have "Move to Trash". Deleting from your Photos library happens in a second step, from the Trash screen, and iOS asks you to confirm it.

The steps

1. On a results screen, select photos or videos and tap "Move to Trash". The code's own comment says this shows no system prompt and nothing is deleted yet. The items stay in your Photos library and are hidden from DeDup's results.
2. Open the Trash (from Settings, the side menu, or the Optimize tab). Select items and tap "Delete", or tap "Empty Trash" for everything in it.
3. DeDup shows its own dialog: "Delete N permanently?" with a "Delete from Photos" button. Its message reads: "They are removed from your Photos library. iOS keeps them in Recently Deleted for 30 more days."
4. After you confirm, DeDup asks Photos to delete the items, and iOS shows its own confirmation. The code documents that if you decline there, nothing is deleted and the items stay in the Trash.

If you're using DeDup as a guest, "Move to Trash" and "Delete" show a "Sign in required" alert instead. The app's text says guests can scan and review.

Where deleted photos go

The delete call in the code is documented as moving the assets to Recently Deleted. The app's text says what that means: "iOS keeps deleted items for 30 days." DeDup does not free the space at this point. The code's comment says space is only freed once the Recently Deleted album is emptied.

I found no code in DeDup that empties Recently Deleted. The app tells you to do it in the Photos app: Photos › Albums › Recently Deleted › Select › Delete All.

What the screen shows afterwards

• The deleted items disappear from the Trash, from the scanner results and from the saved scan results. A duplicate group with fewer than two photos left is removed.
• The Dashboard shows a card: "[size] is waiting in Recently Deleted", with the explanation above and a "Got it" button. The size is the total of what you deleted. The code keeps that figure in memory while the app runs. I found no code that saves it, so don't count on the card after you close the app.
• Photo and video counts on the Dashboard are refreshed, and the deletion is added to the activity log.
• The Deep Storage Tips screen has the same reminder about emptying Recently Deleted.

If a photo was already deleted outside DeDup, it just leaves the Trash. If the delete fails for another reason, the code logs the error and stores its message for an error alert. I didn't check which screens show that alert.

Scope of this post

Checked against: DeDup 1.0.1 source code (iPhone).

Not tested on a device: the wording and look of the iOS confirmation prompt, how long iOS actually keeps items in Recently Deleted, and when the freed space shows up in iOS storage. The 30-day figure is what DeDup's own text says, not something I verified in iOS.