The 4G battle is brewing in the U.S. and while there are currently two competing technologies including WiMAX and LTE being used, most only expect LTE to survive the battle. Everyone but Sprint and Clearwire are backing LTE and Clearwire has cleared the way to move to LTE if it desires.

Despite the murky outlook for WiMAX, there are several markets around the country where WiMAX from Sprint and Clearwire is in use. One of the things missing from these areas so far has been a mobile phone that could operate on the 4G network. So far, only modems for computers have been offered.

A screenshot has leaked from The Shack (formerly Radio Shack) that shows that pre-orders for the HTC EVO will start later this month. That is not a firm date, but the screenshot seems real enough and the time frame meets with rumors that have been circulating about the device. The screen shot reportedly came from the internal employee computer system at The Shack.

The image also lists some of the specs we already knew about the EVO. The device will run the Android 2.1 OS, use a 4.3-inch TFT LCD screen with a resolution of 480x800 and uses a 1GHz Snapdragon processor. The handset also has 512MB of RAM, an 8-megapixel camera, and a 1.3-megapixel front facing camera for video conferencing. Bluetooth, Wi-Fi, mobile HDTV, and HDMI output will be featured along with a microSD card slot for storage.

Phandroid reports that tipsters have claimed that training on the EVO will start on May 24 and the handset has a June 6 launch date. Pricing is still unknown, but one of the many rumors pegs the device at $199.99.