Detect changed data from firebase realtime database

Hello Experts,

I’m using angularfire2 v5 for firebase real time database to show data in my ionic v3 app. I have div with lost of boxes containing the data. Now i just want to highlight those boxes which gets changed value from firebase database, not all boxes.

My current scenario is, i have manage to synchronized my app with firebase realtime database.
But i cannot highlight those record which are changed from firebase realtime database.

My app is mostly like “Stock exchange app”.

Sorry for my bad English. I hope you understand what i mean…