Josh Miller/CNET

If you're in the market for a bargain you can currently pick up a new carrier-unlocked Google Nexus 6 on eBay for just $299 (which converts to £195 or AU$425), or for $349 (£230 or AU$495) on Amazon.com. If you were to purchase the same 32GB model phone directly from Google it would cost $500, £369 or AU$669 -- and that's with a hefty discount on the original price already applied.

The price drop, spotted by Android Police, comes ahead of an event next week in San Francisco, where Google is expected to launch two new Nexus phones. The first will be a smaller Nexus made by LG and the second will be a larger model made by Huawei -- the first ever Google-branded device from the Chinese smartphone giant.

The new phones will introduce Android 6.0, aka Marshmallow, the newest version of Google's mobile operating system software that powers millions of phones and tablets. Nexus devices are traditionally the first to be updated to the latest version of Android, suggesting that if you manage to get your hands on a cut-price Nexus 6 you'll be able to download Marshmallow sooner than other Android phone owners out there.

Nexus phones don't sell anywhere near as well as top models such as Samsung's Galaxy products, but they carry outsized influence by setting an example for what Google hopes Android should be like. Early adopters and developers often like their "pure" Android software, less cluttered than the customised versions that more mainstream Android phones use, and for the fact that Google keeps them current with prompt Android updates.

Despite Google showcasing Android with Nexus, though, the operating system remains as fragmented as ever. With thousands of models using different hardware and software, Android can be more difficult for programmers to support.

Unity

As is the norm ahead of most smartphone launches, leaked pictures of the Nexus 5X and 6P , as they are rumoured to be called, have appeared online. The last Nexus manufactured by LG was the Nexus 5, a relatively inexpensive and popular member of the Nexus family that repeatedly sold out online. It was launched in 2013 and sported a 5-inch screen, and it looks like the new Nexus 5X will be just a bit larger with a 5.2-inch screen. It's also expected to use the same six-core Snapdragon 808 processor found inside the LG G4, something a new leak from Amazon seem to confirm.

The Nexus 6P should have an even larger 5.7-inch display and a fingerprint scanner on the back that looks like a circular version of the sensor on Huawei's Mate smartphones. Nexus phones typically have pretty simple designs, and from what we've seen so far of the 6P, the latest cohort will be no different.

The other common denominator among Nexus devices is that they tend to be cheaper than flagship smartphones from major Android mobile makers. It's expected that the Nexus 5X and 6P will cost significantly less than the likes of the Samsung Galaxy S6 and the HTC One M9, but they won't be anywhere near as cheap as the Nexus 6 currently is on eBay and Amazon. If you want to play around with Android Marshmallow and don't mind year-old hardware, last year's Nexus might be your best bet.