The HTC Touch HD, also known as the HTC T828X or its codename the HTC Blackstone, is a Windows Mobile 6.1 -powered luxury Pocket PC designed and manufactured by HTC,and launched in 2008. Part of the HTC Touch Family, it features a larger, higher-resolution display than those found in most smart-phones available at the time, a 5-megapixel camera, a second front-facing camera to enable Videophone functionality, an accelerometer, GPS, FM RDS radio reception, high resolution video recording capability and SD Micro card compatibility (up to 64 GB). It also features quad band GSM and dual band UMTS connectivity, as well as the proprietary TouchFLO 3D user interface developed by HTC. However, it lacks the left side slide-out keyboard of the HTC Touch Pro.