The Nexus line of Android phones is the Google (GOOGL 1.17%) equivalent of the Apple (AAPL 0.58%) iPhone. It's the only Android family to sport Google's own brand, the devices offer the purest form of Android software, and they're often updated to the latest and greatest software version far ahead of other brands. It's the closest you'll come to Apple's pure brand experience without leaving Android City.

The next Nexus (or perhaps Nexii -- read on!) will be announced on Oct. 29, during the All Things D: Dive Into Mobile conference. The event is conveniently scheduled after Apple's annual iPhone update and before the holiday shopping rush, and Big G has announced Nexus products from this stage before. So what, exactly, will the company unveil?

So far, these smartphones have been manufactured by HTC and Samsung. The best-selling Nexus 7 tablet comes from computer-building giant Asus. And Big G continues to spread the Nexus love around. You might assume that the next Nexus model might come from Motorola Mobility. The company is, after all, a division of Google these days. But the rumor mill points in several other directions without ever saying "Hello, Moto!"

For one, LG just shipped a new high-end Android model to AT&T (T 0.89%), branded as the LG Optimus G.

It's powered by a quad-core Snapdragon processor (read: really, really fast) from Qualcomm (QCOM 0.91%). It also sports a 13-megapixel camera and a 4.7-inch high-definition screen. Rumor has it that Google wants to clean LG's proprietary elements off that phone, install a newer Android version than the 4.0 Ice Cream Sandwich that LG selected, and ship it as the Nexus 4.

Source: AT&T.

But that's not the only potential Nexus on the horizon. Japanese mobile carrier NTT DoCoMo (NYSE: DCM) purportedly leaked a roadmap for the winter, including the LG Nexus model but also Nexus-branded handsets from Samsung and Sony (SONY 0.27%). Photos of the rumored Sony model have been circulating, though they might turn out to be really nice fakes. Details (even rumored ones) on the Samsung model are as rare as chicken lips. But if these phones are coming to Japan, Google would probably bring them over to America soon enough.

If I were a gambling man, I'd put money on the LG model shipping in November while the other two vanish into thin air. Sony and Samsung may very well have new Android phones in the works, but they'll have to wait their turn when it comes to Google-branded Nexus devices.