Editing a Collection (iOS)
Once you've created a collection, you may edit it, along with the items within it, later on.
Tap on the Collections icon (1).
Tap Edit (2).
You may delete collections by tapping on the red circles (3) that appear, and then tapping Delete (4).
To edit a specific collection's contents, tap on its name (5).
Tap Actions (6) to rearrange items, e-mail links to items, or delete the collection.