The stock Android, i.e, the Android OS originally developed by Google without modifications was found to be running on the HTC One. HTC One originally comes with the HTC Sense. The HTC Sense is a graphical UI developed by HTC Android, Brew and Windows Mobile devices.
But the consumers’ anticipation of receiving the new Android on the bloc as soon as it is released makes tough for the HTC phones to be launched with Sense. May be an HTC One sans Sense and pro vanilla Android may increase the attractiveness of the device. The sources anticipate such a device very soon, but there is no exact date as such.