This is a prototype of an unreleased WebOS smartphone HP codenamed WindsorNot. Obtained by webOS Nation, the smartphone has a 4-inch touchscreen display with 233ppi (800 x 480), runs webOS 3.x, the same version of the dead HP TouchPad, and has a home button instead of a gesture area.
According to webOS Nation it was developed under Jon Rubinstein and was intended to be released in 2011. HP come to the conclusion that the WindsorNot would need more development time, so it would of not come until 2012. This caused AT&T to lose interest in the smartphone as by then they wanted LTE devices and the WindsorNot wasn't capable.
So the last webOS smartphone never actually made it into consumer hands, but would it have done any better than the Touchpad against strong competition? Unfortunately I doubt it.
Source: webOS Nation