The original HTC HD2 which ran Windows Mobile with the predecessor to HTC Sense, TouchFLO 3D, on top was quite popular, The HTC HD7 was the next phone with the HD name and it ran the new Windows Phone OS and according to rumors and some reports there maybe an HD8 round the corner.
HD8 was spotted in the “I’m a WP7” application and reportedly runs on the network of Romanian wireless carrier Vodafone, WPCentral reports and according to information it is only running 7740 firmware and not Windows 8 as some would’ve expected and it first appeared on December 30th, 2011. Well we should take these reports with a pinch of salt but a new addition to the HD seems logical and it may still come to the market with Apollo.