Google (GOOG) apparently isn’t wasting any time in getting right down to it with its impending wireless service.

Word emerged in late January the search giant had signed reseller deals with telecoms Sprint (S) and T-Mobile (TMUS), the third- and fourth largest wireless carriers, to sell wireless service directly to end customers in rebranding, wholesale deals, effectively making the search giant a mobile virtual network operator, or MVNO. Then, in short order, more buzz surfaced that Google’s wireless service could enable users to locate the best signal from multiple carriers rather than relying on a single network to provide cellular or Wi-Fi connection.

Now, Google is said to be only weeks away from kicking off its wireless network but with one fairly substantial caveat–the service only will work on its latest Nexus 6 smartphone, the Wall Street Journal reported.

The explanation for confining the service to the Nexus 6 has to do with toggling back and forth between Wi-Fi, Sprint and T-Mobile’s network to find the best signal, a capability that requires Google to engineer hardware and software changes that, at least for now, it can only execute on its own devices.

And, as the Journal suggested, the Google-designed and Motorola-built Nexus 6 is a perfect platform for the company to showcase to other Android handset makers its wireless service. Android 5.0 enables users to switch between wireless networks based on optimizing app performance.

At Mobile World Congress (MWC), Sundar Pichai, Google products senior vice president, hinted in a keynote that the results of Google’s MVNO mobile network project will be evident shortly.

“The core of Android and everything we do is to take an ecosystem approach and [a network would have] the same attributes,” he said. “We don’t intend to be a network operator at scale. We are actually working with carrier partners. Will announce something in the coming months.”