Avengers Initiative

Avengers Initiative was a standalone game for mobile devices, primarily running Apple's iOS and Google's Android operating systems. The game was made by Wideload Games, a game developing company acquired by The Walt Disney Company under the Disney Interactive name.

The game is connected to Marvel: Avengers Alliance (MAA) through Marvel XP, and is the first game other than MAA to use Marvel XP. The inter-connectivity allows for a shared reward system, which is based on Marvel XP Awards. This game closed down on April 26 2014.

Android
The following devices are compatible with this game:
 * HTC Evo 4g
 * HTC Incredible 4g
 * HTC One X+
 * HTC One X (Tegra Version)
 * LG G2x
 * LG Nitro HD
 * Motorola Droid 3
 * Motorola Atrix 4g
 * Motorola Photon Q 4g
 * Samsung Galaxy Nexus
 * Samsung Galaxy SII
 * Samsung Galaxy SIII
 * Samsung Galaxy Note
 * Samsung Galaxy Tab 7.7
 * Asus Nexus 7
 * Asus Transformer Tablet

iOS
Requirements: Requires iOS 4.3 or later. This app is optimized for iPhone 5.

The following devices are compatible with this game:
 * iPhone 4
 * iPhone 4S
 * iPhone 5
 * iPad 2 Wi-Fi
 * iPad 2 Wi-Fi + 3G
 * iPad (3rd generation)
 * iPad Wi-Fi + 4G
 * iPad (4th generation)
 * iPad Wi-Fi + Cellular (4th generation)
 * iPad mini and iPad mini Wi-Fi + Cellular

Windows Phone
All devices running on Windows Phone 8 are compatible with this game.

The Windows Phone version of Avengers Initiative does not feature Marvel XP connectivity.

Characters
Hulk and Captain America were available to play. You begin with Hulk unlocked, and could unlock Cap's story through in-game currency.

It was originally announced that Thor and Iron Man were originally going to be playable characters as well, but never appeared as further work on the game was quietly cancelled.

Story
Someone infiltrated S.H.I.E.L.D. and let the prisoners in the Vault escape. Play as Hulk to recapture the prisoners or Captain America to find the mole in S.H.I.E.L.D..