If you had any doubt how serious RIM is about helping developers port their apps from Android an iOS then look no further than this. RIM has posted a guide for iOS developers showing them how to port their app to Cascades. They have also posted one for Android NDK developers and iOS NDK developers to port their native apps and games to the BlackBerry 10 Native SDK. RIM also has a great guide mapping native iOS and Android NDK commands to BlackBerry 10 Native commands.
Check them out below: