The Blu Win HD is not comparable to the 640, the Blu Win HD LTE can go toe 2 toe. It has a better processor 410 64-bit vs 400 32-bit, FFC 2MP vs 0.9 MP. The 640 has NFC (I will never buy a phone again without it), removable battery, and Glance. Both have FM radio, a feature that's never talked...