Watch out iPad! Google is reportedly working on its own custom Android-powered tablet.So what a Google Android tablet could be and how it might compare to Apple’s iPad. Google’s Android Market for apps allows anyone to submit and publish programs without scrutiny. Android-powered devices — with the exception of those that run on AT&T  — also let users download apps from unofficial third-party sources. One would imagine these qualities would be among the basic tenets of a Google-made Android tablet.

Along those same lines, a Google Android tablet would likely provide support for Flash — something Apple has long forbidden on its mobile computing devices. The existence of an open app marketplace could also mean immediate support for tethering, as we’ve seen happen via third-party utilities on Android phones. And, of course, any Android tablet would presumably provide feature-rich apps for Google services such as Gmail and Google Voice, something Apple also does not permit.

So whether or not Google ends up building its own tablet, numerous new options will soon be headed our way. The iPad may have been the first serious contender, but it won’t be the only one for long.