You can earn additional rewards by completing daily challenges.

 

These short challenges may require searching certain scenes, finding donuts, and collecting certain beads in match-3 games. You can complete six challenges daily, three at a time. You can also spend diamonds to switch to a different challenge by tapping the button on the upper-right corner of the challenge card.

 

Completing daily challenges will reward you with items used for local mementos, and completing all six challenges within a day yields even more resources.