Given Apple's status as the most powerful promotional partner in the mobile gaming world, it's no surprise most developers are keen to keep in its good books.

There are many ways to do this.

Making great games and releasing them on the App Store ahead of Google Play is a key one.

As is supporting all the latest iOS features and new Apple hardware.

And it's days like today when all that hard work starts to pay back dividends.

Apps for Earth

As part of Apple's Apps for Earth campaign with WWF, which runs until 24 April, some of Apple's favourite developers and games are going green (and blue) and getting extra App Store love in return. 

To some extent, it's a list of usual suspects and big brands, with Rovio, Disney, Kabam, EA, King and Glu Games all represented.

But there are some smaller players.

Finnish developer Seriously is highlighted, as is Spanish dev Social Point (both also featured on our Top 50 Developers of 2016 list - #19 and #37 respectively).

Trivia Crack dev Etermax (#24) is there too, while the smallest outfit is London brain training studio Brainbow.

IAP for Earth

Each game has added some additional 'ecological' Apps for Earth content (typically a special IAP) - although some have obviously spent more time on integration than others.

We are looking forward to our team of Ewoks saving Endor in Star Wars: Galaxy of Heroes, however.

All proceeds go to WWF.

The full list of developers/games and content is below:

• Angry Birds 2 (Rovio) focuses on protecting our oceans with a limited-time event that includes three exclusive levels and an all-new power-up. Players will be challenged to stop the dastardly piggies from overfishing.

• Best Fiends (Seriously) players can engage in an Apps for Earth quest consisting of fun puzzle levels set in the Yangtze River region in China. To help solve the puzzles, players can purchase unique Panda Pals for a limited-time.

• Candy Crush Soda Saga (King) features a live in-game event, Bamboo Hill, which players can experience on the weekends of April 15 and April 21 to help conserve our planet.

• Cooking Dash 2016 (Glu Games) features an all-new "Eats for Earth" show for players to enjoy. With help from can-do waitress Flo, players work to prepare a menu of new dishes using sustainable ingredients. Aspiring chefs can also purchase in-game items to help cook responsibly.

• Cut the Rope: Magic (ZeptoLab) offers all-new and exclusive puzzle levels where Om Nom magically transforms into an adorable panda inspired by the now famous sneezing panda meme.
• Disney Infinity: Toy Box 3.0 (Disney) players can purchase an exclusive Apps for Earth bundle consisting of Nick, Judy and Baloo figures, as well as Power Disks. Players will also experience a set of new Toy Box levels.

• Dragon City (Social Point) features the exclusive Panda Island, which includes six new dragons inspired by WWF's core focus areas.

• Hay Day (Supercell) players can purchase a new Bag of Diamonds from the game's shop to receive an exclusive Panda Statue decoration and the opportunity to display the WWF logo on their roadside shop for the duration of the campaign.

• Hearthstone (Blizzard) players can purchase the new hero, Kahadgar, who will unlock arcane power and protect against evil.

• Jurassic World: The Game (Ludia) will feature exclusive content such as new "Legendary" dinosaurs, brand new decorations, energy-generating turbines and more.

• Kendall & Kylie (Glu Games Inc) players can participate in a new in-game quest and event supporting water conservation, while earning ocean conservation-themed clothing, accessories and more, through the purchase of unique water droplets. Plus, players can take and share selfies inside the exclusive WWF-branded selfie booth.

• LINE: Disney Tsum Tsum (LINE) players can purchase a Ruby to earn a very special, limited-edition Earth pin that users will be able to display with pride.

• MARVEL Contest of Champions (Kabam) will offer a limited-time bundle called the "WWF Power Pack" which includes 3-star Hulk and a Go Green ticket to access a special in-game quest.

• Peak (Brainbow) players will protect the environment while training their brain; players will guide Billy the Hawksbill turtle through the sea, eating as much jellyfish as possible, while dodging plastic bags, fishing nets and other ocean obstacles.

• SimCity BuildIt (EA) players can create ocean preserves to safeguard marine life, grow and sustain lush forests, and create wildlife habitats to protect endangered species.

• Star Wars: Galaxy of Heroes (EA) fans will have a chance to assemble their Ewoks in an epic battle to protect the forest moon of Endor; players can also purchase store bundles and participate in a multi-tiered special event where players will need to form their squad of Ewoks to fight against the Empire and push them off the forest moon for good.

• Trivia Crack (Etermax) players can challenge themselves to WWF-inspired facts and trivia when they purchase custom characters based on each of the six WWF pillars.