25 apps that are going Apple (RED) for the holidays

About six months ago, Apple approached the designers of some of its most popular app-store products and asked them if they would modify them to help promote the company's two-week fundraising campaign (from Monday through Dec. 7) for (RED), which fights the spread of HIV/AIDS particularly in developing nations.

Those purchasing the app for the first time will see their money go to (RED), while those who already own the apps will be able to contribute via various in-app upgrades. The 25 participating app makers and their (RED) characteristics are:

• Angry Birds players can perfect their bird-flinging with (RED)'s Mighty Feathers and challenge themselves to a bonus golden egg level.
• Bubble Witch 2 Saga offers new (RED) levels across all 17 episodes of the game. Gold bar currency purchases will be donated to (RED).
• CSR Racing delivers new in-game thrills with the highly anticipated Mercedes Benz-AMG GT.
• Clash of Clans warriors can prepare for battle with special edition (RED) gems and display a (RED) badge of honor on the village's town hall.
• Clear's users can perfect their organizational skills with a new (RED) theme which appears automatically with all new downloads.
• Cut the Rope 2 unveils a wide selection of (RED) items including a new red hat, red touch print, red balloons and a red ginger cookie.
• Despicable Me: Minion Rush reveals a new Lifeguard minion that helps players boost their banana collection skills by 200 percent.
• DJay 2's spin tables turn (RED) and offer DJs a special sound pack.
• FarmVille 2: Country Escape players can "Roll out the RED Carpet" and purchase limited-time items such as the Cozy Cow, St. Bernard and more.
• FIFA 15 Ultimate Team players can compete in a (RED) Tournament and Team of the Week event. All winners will be awarded football superstar and (RED) Ambassador Rafa Marquez.
• Frozen Free Fall unveils a magical new (RED) Challenge in the Kingdom of Arendelle, and offers an exclusive combined offer of 1 power-up, 1 snowball and 3 lives.
• GarageBand users can now purchase an exclusive collection of 300 guitar, bass, synth and drum loops to create even more amazing music.
• Kim Kardashian: Hollywood's aspiring celebrity players can treat themselves to (RED) items including Beats (RED) Solo2 headphones. Kris Jenner, the first family member to join Kim's in-app world, will make her in-game debut on December 1.
• Head's Up! competition heats up with an exclusive new deck featuring red words.
• The Human Body debuts the Immune System feature, educating users on how the body fights pathogens. The accompanying handbook features a new section on HIV/AIDS.
• Kitchen Stories Cookbook will offer a special-edition holiday recipe pack, featuring dishes from renowned chefs Mario Batali, Martha Stewart, Luke Holden and Michael Lomonaco.
• Monument Valley offers a whole new chapter of Ida's Journey, marking the final new feature of the game.
• Over customers have access to a wide selection of (RED) fonts and inspiring artwork, specially created by six artists. Users can share photos with the (RED) brackets overlay to help spread awareness.
• Paper by FiftyThree enthusiasts can enjoy a new (RED) Essentials Pack including Sketch, Outline, Write, Color and Mixer tools.
• Puzzle & Dragons players have exclusive access to the new (RED) magic stone.
• Rayman Fiesta Run introduces a new (RED) edition to their wacky Fiesta world, and players can purchase a pack of three new costumes for Rayman, Globox and Teensy characters.
• Star Walk 2 users can learn more about Mars with the comprehensive new RED Planet feature.
• Sims FreePlay features a special community challenge that unlocks various rewards, and players can purchase limited-edition (RED) items such as a swimming pool, party plane and piñata.
• Threes! turns (RED) with a limited-edition (PRODUCT)RED theme.
• Toca Boca paints Toca Town (RED)! Kids can discover new (RED) diamonds, sample (RED) ice cream in the app and look for other surprises throughout the game.