iCloud Photo Sharing lets you share photos with friends, family, and anyone else by creating a shared Photo Stream. Once you add photos, your subscribers can like or comment on them — and even add their own images, if you give them permission. But what if you want to delete a picture later on? Here's how you can remove it from the shared stream and your subscribers' devices.
How to remove photos from a shared Photo Stream for iPhone and iPad
Launch the Photos app on your iPhone or iPad.
Tap on the Shared tab within the bottom menu.
Tap Sharing in the upper left corner to access your shared streams.
Tap the name of the stream that contains the image(s) you'd like to delete.
Tap Select in the upper right corner.
Tap on the photos you'd like to delete.
Tap on the trash can icon in the bottom right corner.
Confirm you'd like to delete the selected images in the popup menu.
The photos you've selected will then be deleted from the shared Photo Stream, and de-synced from subscriber devices. Note: remember that if people have saved images to their Camera Roll from the stream, those copies will not be deleted. So just like anywhere else on the Internet, be careful what photos you put in shared streams.