In the mobile app, you can activate Memories. The Memories feature shows photos you took on the same day one year ago, two years ago, three years ago etc... The memories appear as bubbles above the timeline, so you can easily relive them from day to day.

To view the memories, tap the bubbles above the timeline. Photos from the year you chose will show automatically, but you can also tap a photo to show the next. The memory bubbles will be visible all day, so you to view them as many times as you like.

You can turn the Memories feature on/off in the mobile app settings.