To delete a photo in the Web App hover over the photo you wish to delete. Click on the circle in the bottom right of the photo and a tick will appear.
A menu bar will then appear at the top of the page. Click on the "Trash Can" icon to delete the image.
You can also delete multiple photos by clicking on the first photo you wish to delete, holding Shift on your keyboard, and selecting the last photo as well. All photos in between the two will be selected, and you can click on the "Trash Can" icon to delete them all.
To delete a Narrative Moment on the Web App, click on the three dots in the bottom right corner of the Moment. From here you can choose to either Share or Delete your Moment.
To delete a photo or Narrative Moment on the Smartphone App, enter your Moment and tap on the 3 dots in the bottom right of the photo you wish to delete.
A menu will appear and from here you can delete either the photo or the Moment.