HTC HD 2 is a Windows Mobile 6.5 phone with powerful hardware specifications and that’s why several developers were in try to make it dual boot device. So, Pop45398 at XDA released RunDroid app for HTC HD 2 that makes it dual-boot with Windows Mobile or Android.
HTC HD 2 owners who want to make their device dual-boot must read following instructions to proceed.
Dual Boot HTC HD2 with Rundroid
Keep Android OS on your HTC HD 2’s SD card
Download RunDroid and run as File Manager through Windows Mobile
Set RunDroid on “Autorun” mode
Onwards, whenever you boot your HTC HD2, it shows “Boot Selection” menu with Windows Mobile or Android options, so chose as per your requirement
Note: If you want dual-boot of Windows Phone 7 or Android on your HTC HD2 then head to XDA to know detailed instructions to do so.