Google is the major driving force behind Android development, while Samsung is reigning as the biggest manufacturer of Android devices. The two companies have collaborated in the past, but now they have approached the same territory from different angles.
The Google-designed Nexus line is taking its first step into the phablet field, while Samsung has essentially started the game. However, Google came here to promote its software, its cloud services and social network, while Samsung is all about selling the end-user hardware.
With Motorola's expertise, the search giant put together an excellent device - more expensive than some had hoped, but priced reasonably considering its late-2014 flagship features. It has the best AMOLED screen outside of Samsung, housed in a premium design, powered by a top-of-the-line chipset, with goodies like stereo speakers and a ring flash to sweeten the mix.
It's strange that it's Samsung, the hardware-centric company, which offers the more compelling software features. There are rich multitasking options available on the Galaxy Note 4, but individual apps had distinct advantages too. The camera has more modes, the music player has more to offer audiophiles, the gallery doesn't pretend there's only one social network and so on.
As for the hardware, until the Galaxy S6 comes out, the Note 4 is the best phone that Samsung has put together. Using its own screens and on some units its own chipset too. RAM and storage are also Samsung made. In the 2015 generation "Samsung" will be stamped on even more components.
Good sales of the Galaxy Note 4 also mean that Samsung's component factories are doing great. For Google success looks differently - the stereo speakers will get you to try Play Music, the camera will have you uploading to Google+ and YouTube, the fast chipset will let you play the best games from the Play Store and the large screen is the perfect place to tap into Play Movies on the go.
With different goals, it's hard to call a definite winner. It doesn't help that both phones offer almost identical performance, though Samsung's customized software earned it a win in the web browsing performance. The Galaxy Note 4 also lasts longer while browsing the web and much longer when playing videos, for general usage too.
The S Pen is in a category of its own, for now at least, and the screen offers better flexibility in color rendering and sunlight legibility. The camera produced slightly better stills and video, the same goes for the audio output quality, too. However, the single loudspeaker won't tempt you to try Samsung Milk Music and, unlike the Galaxy S5, there's no added water resistance, something that the Nexus 6 has (to an extent).
The Motorola Nexus 6 is strong where its opponent is weak, with stereo speakers, basic water resistance and wireless charging. Google is a modern software company and its UI designs reflect that. Lollipop's Material Design has gotten so popular that web sites have started using it, never mind Android apps. And with a Nexus you have a promise of fast track software updates straight from the source.
We think the different nature of the makers of the Samsung Galaxy Note 4 and the Motorola Nexus 6 reflects the type of consumer that will buy either product. The Galaxy Note 4 is self-contained and focused on physical excellence, while the Nexus 6 tries to deliver all the cloud services Google has on offer to as many people as possible.