Designed by HTC, the myTouch 3G will be available for presale to T-Mobile customers on July 8 and will sell for $200 for users who sign a two-year service contract. The phone, which features a 3.2-inch touchscreen, is being released just under a year after T-Mobile launched its first Android-powered smartphone, the HTC G1.

Android is a Linux-based open source mobile platform that Google debuted in 2007. Google has long said that the goal of the platform would be to spur innovation within the mobile development community and also to give users the ability to switch to new carriers without switching their mobile devices.

The phone will run on T-Mobile’s GSM-based Universal Mobile Telecommunications System (UMTS) 3G network and on Wi-Fi networks. T-Mobile was the last major wireless carrier to launch its own 3G network, as the company only put its UMTS services online last May.

The myTouch 3g is one of three other Android-based phones that are expected to hit the market in the near future. One of the phones, known as the HTC Magic, is already available in Spain and the United Kingdom and is expected to be released in the United States sometime in the near future. The phone was approved for use in the United States by the FCC this past March and is likely to be carried by T-Mobile. The HTC Lancaster, meanwhile, is slated to be released on August 3 by AT&T and is being described as a “social messaging device” that features a slider QWERTY keyboard.

This has been a particularly busy time for smartphone releases, as the Apple iPhone 3GS and the Palm Pre have generated significant media attention and sales. Other smartphones due to hit the market over the next few months are the HTC Snap, the Nokia N97 and a sequel to the BlackBerry Storm.