Google worked with Motorola to design the Nexus 6, so the new smartphone looks very similar to the Motorola Moto X. It has a contoured aluminium frame, and a smooth plastic back available in cloud white or this midnight blue.
The iPhone 6 Plus has a completely aluminium back case, available in silver, gold and slate grey, so looks a bit more premium.
The Nexus 6 is thicker and heavier than the iPhone 6 Plus, but Google has managed to squeeze the 6in screen into a body that's not hugely different in size to the iPhone 6 Plus with a 5.5in display.
If you're after a smartphone that sits firmly in the phablet category, both of these smartphones have suitably large displays. The 6 Plus boasts an impressive 401ppi Retina HD display, but the Nexus 6 has a brilliant 493ppi QuadHD display.
Inside the Nexus 6 is a Snapdragon 805 processor, making it a powerful smartphone. It has 3GB of RAM while the iPhone 6 Plus has 1GB.
The iPhone 6 Plus is powerful, too though, with its 64-bit A8 processor and M8 motion-co-processor, and beats the Nexus 6 in graphics and browser benchmark tests.
There are two capacity options for the Google Nexus 6: 32GB and 64GB. There's no microSD slot, though. The iPhone 6 Plus also lacks the microSD slot but does offer 16GB, 64GB and 128GB options.
Both the Nexus 6 and iPhone 6 Plus have 802.11ac WiFi, Bluetooth 4.1 and NFC connectivity options, in addition to 4G LTE. However, NFC is restricted to Apple Pay on the iPhone.
One of the features on the Nexus 6 that we'd love to see on iPhone is dual front-facing speakers. The Nexus 6 doesn't have the fingerprint sensor found on the iPhone 6 Plus, though.
The camera on the rear of the Nexus 6 is 13Mp, compared with the iPhone 6 Plus's 8Mp, but the iPhone has bigger pixels. Both cameras are impressive, and both have dual-LED flash and optical image stabilisation.
The front-facing camera of the Nexus 6 is 2.1Mp while the iPhone 6 Plus's front-facing camera is 1.2Mp.
The Nexus 6 has impressive video capabilities too, with support for 4K video recording from the rear-facing camera and 1080p video recording from the front. The iPhone 6 Plus is capable of 1080p video.
The iPhone, of course, runs iOS 8 and will be updated to iOS 9 when it arrives later this year. The Nexus 6 runs Google's new Android Lollipop and will also get the latest updates as they arrive.
Software is a huge part of the decision making process between these two smartphones, and it really comes down to personal preference. However, if you're an Android user who's spent lots of money on apps and other content for their smartphone or tablet in the past, remember that switching to iOSwill mean you'll have to cough up cash again to download those apps for Apple's operating system.
The Nexus 6 starts at £499, while the iPhone 6 Plus is more pricey at £619.