In design, the device seems to borrow quite a bit from T-Mobile’s Sidekick, and its touchscreen GUI owes a thing or two to Apple’s (AAPL) iPhone. Which makes perfect sense, since that’s the device it’s clearly intended to compete with. The G1 will run on both 3G and Wi-Fi and be tethered to the T-Mobile (DT) network. It will come preloaded with a version of Amazon’s MP3 store and Android Market, an application store similar to Apple’s App Store. And it will support and sync with the broad spectrum of Google (GOOG) apps–Google Talk, Google Calendar, etc. Its browser is something the dev team refers to as Chrome-Lite, a mobile version of Google’s new Webkit-based Chrome browser.

Oddly, the G1 has no built-in video player. Odder still, it has just 1GB of memory. T-Mobile has helpfully outfitted it with a 1GB/month bandwidth cap, though.

The G1 supports PDFs and Microsoft Office documents as well. Email will be handled through Gmail; there is no Exchange support, though presumably, engineers developing for Android Market will fill that void in short order.

Oh, the device offers copy-and-paste functionality. Hear that Apple?

It will arrive at market Oct. 22. Price: a highly-subsidized $179.