1. To mark events or notifications as "Read", click on the ≡ icon on the top left-hand corner to open the side menu of the app. Then, select your Location.
2. Click on the "Events" tab on the bottom bar of the app where you will see a list of all your events for that Location.
3. To mark a particular event as "read", click on it or you can mark all events as "read" by scrolling down and selecting "Mark All As Read".
You can watch videos on how to mark events as "read" by clicking on the below links:
Marking Events as Read (Android)
Marking Events as Read (iOS)