Weekend Download: April 23 - 29

1. Earth day event

The event for Earth Day has begun. It features increased spawn rates and Stardust for Grass-, Water-, and Ground-type Pokémon. The event was only scheduled to last 48 hours, but it will now end at 1:00 P.M. PDT on April 30. Additionally, this event has also given us Shiny Wailmer and Shiny Wailord.
SOURCE: Niantic, Community Reports

2. Research task shakeup

Changes will soon come to Field Research tasks and Research Breakthrough encounters. Starting at 1:00 P.M. PDT on May 1, new "skill-based" Field Research that centers around Electric- and Flying-types. Zapdos will also replace Moltres as the Legendary encounter from Research Breakthroughs for the month of May.
SOURCE: Niantic

3. A new update

A new update appeared in the app stores this week. Dataminers discovered that there were some new additions that went unannounced. New research tasks, the Fast Attack Smack Down, and a "Mythical" search term were programmed. Additionally, more code has been added for the PokéStop submission feature.
SOURCE: The Silph Road's Datamine Report

4. EX Raids

As expected, people have reported another wave of EX Raid Passes. The Raids will take place on May 7 or May 8, depending on where you are in the world. This comes shortly before the next EX Raids on April 29 and 30. To prepare for your Mewtwo, we recommend reading our Mewtwo Raid Guide.
SOURCE: Community Reports

5. Weekend trivia

This Pokémon's body is made of an incredibly-hard metal that is said to have come from another world. It is unknown what this Pokémon eats. Who's that Pokémon: Dialga, Metagross, Bronzong, or Registeel?

Voters were highly in favor of Metagross, but the correct answer is Registeel.
TRIVIA SOURCE: The Pokémon Company's Official Pokédex