LG Optimus 2X

There is only word for it, fast. This phone is dead fast. With the dual core Tegra core processor the applications virtually fly. Launching and Switching apps will be over in the blink of an eye. And it also provides highly responsive gaming experience as well.

Measuring 4 inches diagonally, it has 16 million colors and a WVGA resolution of 480x800. The overall phone feels smooth and lightweight--it measures 4.95 inches long by 2.5 inches wide by less than half an inch thick and weighs in at around 4.9 ounces. Other features include Wi-Fi with portable hot-spot capability, full HD video playback and recording, a gyro sensor, DLNA support, an 8-megapixel rear camera and a 1.3-megapixel front-facing camera, and HDMI mirroring.

This one runs on Android 2.2 but I bet it could be upgradeable to 2.3 or even the new android version the honeycomb. It supports quad-band GSM and tri-band UMTS. This price of this phone is around 500$.