One of the reasons why you have duplicate photos or data in your iPhone is when you recently set up the device and restored your data. Those that were backed up in the iCloud will be downloaded into your new iPhone, which might already contain some of your photos.

Time Needed : 3 minutes

This results in duplicates but Apple already thought of that and it made it easier for you to manage your duplicate data.
The process of deleting duplicate photos and even videos is easy and simple. Here’s how you do it:

Go back to the Home screen and then tap Photos.

The Photos app is the default pictures and videos manager on your iPhone.
Tap Albums at the bottom of the screen if it’s not selected yet.

It will show you the list of albums or directories that you can manage.
Scroll all the way down and then tap Duplicates.

It is one of the last options you can find and it’s filed under Utilities.
Tap Merge and the photo and its duplicate will be merged into one picture.

They will then be removed from the Duplicates album.
You may also tap Select at the top-right corner of the screen.

This will give you the option to merge or delete the duplicates.
You may tap Select All at the top-left corner, or select the duplicates one by one.

We suggest that if you have important photos, select them one by one to minimize the risk of losing them.
Tap Merge at the bottom of the screen to merge the photos you’ve selected with their duplicates.

Bear in mind that the photos will only be merged with their duplicates and not with others.
You may also tap the More options icon at the bottom-right corner of the screen and select a different option.

You can Adjust Location, Data & Time, add them to an Album and many more.
But if you want to remove the ones you selected, tap the Trash bin.

You will have to confirm if you really want to delete them.