| MRAID_ENV | Host-provided global object with environment details (version, vendor, supports, placementType, positions, sizes), set before mraid.js loads — reliable MRAID detection and early initialization. |
| exposureChange | Exposure percentage, visible rectangle and occlusion rectangles — the correct basis for viewability measurement. |
| audioVolumeChange | Audibility measurement: volume changes delivered to the ad. |
| open | Open URLs / deep links outside the ad (external browser, in-app browser, other apps). |
| unload | Graceful self-unload and host notification for broken or unwanted ads. |
| setOrientationProperties | Control device orientation behavior (with getOrientationProperties). |
| getCurrentAppOrientation | Read the current app orientation and lock state. |
| getLocation | Device location access behind the location supports feature. |
| initVpaid | VPAID appendix integrated: optional host bridge for MRAID+VPAID creatives. |