This emulation is done using a tool that emulates an x86 environment on the ARM system and allows RT to execute API calls without a major use of system resources. According to the developer, he is planning on releasing a standalone tool so that its automatically emulated each time Surface RT boots or each time the app is executed. It works with a handful of applications as of right now, but future releases should support a wider variety. In the video demonstration he is running Heroes of Might and Magic III. The steps involved with this hack are pretty simple and outlined on the XDA website in greater detail."
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