Collect the Eggs is a limited time event that gives boosters as rewards for Collecting Eggs that are hidden in bubbles of levels.
24 hrs before the event starts a Pre-Event Countdown icon will appear on the Map, showing the remaining time until event starts.
You can tap the event icon on the map to access the Event Hub Screen. The Event Hub Screen informs you about the event and has a timer which counts down to the end of the event.
The various rewards are shown along the progress bar. The text below the bar shows you the exact number of collectibles that have so far been obtained out of the total. The total is the highest reward tier.
Event Objective Counter and Continue Screen
During gameplay in level, you see an objective counter placed beside the bird character in the bottom left corner of the game screen. The counter shows players how many collectibles they have collected in the level.
Level Complete Screen and Reward Unlocked Screen
At the end of the level you presented with the level summary screen. A quest widget will show your current progress towards the next event milestone. Any eggs you've collected are added to your total.