The quickest way to get the new Google KitKat Android operating system? Go out and buy a Google Nexus 5, which is available right now and for a reasonable price.Yes, Google has another Nexus flagship on the market, one that has been rumoured to death for weeks. Looks like a lot of that rumour was actually fact too, with little here that we hadn't already guessed.Of course, heading things up is that new operating system, you can find out all about that here. But the hardware side isn't to be sniffed at. That includes a 5-inch 1920 × 1080 display (445 ppi), a 1.3-megapixel front-facing camera and an 8-megapixel rear-facing camera with optical image stabilisation (OIS), Photo Sphere for joining together 360-degree shots and HDR+ for burst shots (automatically choosing the best).On top of that, there is a 2.3GHz quad-core Qualcomm Snapdragon 800 processor, 2GB RAM and all the connectivity you would expect (including 4G, NFC and Bluetooth 4.0). There's a choice of either 16GB or 32GB of storage.It weights in at 130g and is sized at 69.17 x 137.84 x 8.59mm. If you want one, the Google Nexus 5, is on sale today (1 November) in a choice of black or white, selling from £295 (16GB model) SIM-free.If you want the bigger version, O2 will be exclusively selling a 32GB version of the Nexus 5, but you'll have to do the contract thing. It is on the O2 Refresh tariff from free on a £32 a month plan, which gives you 600 minutes, unlimited texts and 750MB of data.