This is without a doubt the best phone I have ever owned. I recently upgraded from a Galaxy S3 and the difference is night and day. The GS3 was a good phone, but the Note 4 is blazing fast, without a hint of lag or UI stutter. It nearly triples the battery life of the GS3 and the screen is so much better that I feel almost blind going back and using my GS3 to transfer files.
The S-pen is a pretty incredible tool for artists and business users. It is fully pressure sensitive and using it is very similar to using a Wacom digitizer, especially since the screen is such a high resolution. Everything you draw looks smooth and sharp. The S-pen is also very handy for taking notes and there are some cool apps that will translate your handwriting into editable text which makes note taking, email, etc. very quick and easy.
Physically the phone looks and feels like a premium device. It has solid weight but isn’t to heavy. It feels solid, and the screen, metal rim and "leather" back come together to give the phone a high-end appearance. The leather back is actually polycarbonate plastic, but on the black model it has a soft coating that makes it FEEL like real leather.
People may complain about the size of the phone, but if you are buying a Note 4 you know you are buying a large device so I think people need to get over it. There are smaller phones available if that is what you need.
At first I was afraid this phone would be too large for me, but using it one-handed is easier than you would think. First the phone is well balanced so it feels good to hold, even without a case. Typing is also a great experience on this phone, as the keyboard is bigger to match the larger screen. I find myself much less often hitting the wrong key and relying on auto-correct to fix my error.
Next there are some clever software features that make one-handed use easy such as the "reduce screen size" feature that can be activated by sliding your thumb from the edge of the screen, to the center, and then back to the edge. This "windows" the entire UI and allows you to scale the window so that you can reach every screen control with your thumb. You can do this from either side of the phone so it is good for lefties & righties.
There is also a "side key panel" that can duplicate the hardware Android button functions if you find them too hard to use at the bottom of the phone. You can position this almost anywhere and it acts like a floating dock over most apps and the home screen so you always have it accessible. it slides into the side of the screen with a small arrow visible so you an tap it to bring these buttons up whenever you need them.
There are a lot of clever features such as these that make the phone easy to use despite its large size. These features combined with an amazing screen, incredible battery life and solid construction make this a hard phone to beat!