Of course the iPhone isn’t the only smartphone designers come up with concepts for, and we have a concept for a successor to the HTC HD2 for you today in the form of the HTC HD3 concept designed by Antoine Brieux, reports an article over on concept-phones.

As you are probably aware the HTC HD2 isn’t upgradeable to Microsoft’s latest operating system, Windows Phone 7 Series, but apparently this HTC HD3 would be a Windows Phone 7 handset.

The HTC HD3 specs go like this, a 1.5GHz Snapdragon processor along with 1GB RAM memory, 1GB Rom, 16GB internal memory and microSD expansion, a 4.5 inch AMOLED multi-touch screen, an 8 megapixel camera with dual LED flash and 720p video, a front facing camera, 3G, 4G, WiFi and Bluetooth, HDMI, USB and 3.5mm jack.

The HTC HD3 would be powered by an 1800mAh battery, run Windows Phone 7 Series operating system of course and all neatly crammed into a 10mm think housing.