The idea of having a device with a screen diagonal measuring 5.3 inches seemed crazy in 2011, but that was the time the first Samsung Galaxy Note got released and it was very well received. The idea was very well implemented as it integrated some of the best specs at that time being one of the first devices to use an HD screen, but also it introduced a stylus called the S-Pen offering more functionality than just being able to draw with it and becoming an integral part of the UI. Thus, the first phablet was born. The successor came a year later upgrading its internals and making the S-Pen a little more comfortable and better integrated with the UI as well as being able to detect 4 times more levels of pressure. The Note 3 came another year after with an even larger screen but keeping the same size of the device, the resolution of the display was significantly better and the internals all received noticeable upgrades and giving the S-Pen more functionality than ever before.
The Note 4 was introduced last September and the hardware was improved by using a metal frame in its construction and the screen, while keeping the same size as its predecessor, uses a much higher QHD resolution. The camera on this device is still considered to be one of the best thanks to its OIS system. The S-Pen recognizes even more pressure points and they made it slimmer but kept it comfortable. It's got to the point that we consider the Galaxy Note series a second flagship for the company. There's not much information regarding the Galaxy Note 5, but it is known to launch in September.
Now, a patent has been registered to a small but significant improvement to the mechanism of the S-Pen. It's an auto-eject function that could be controlled by a gesture or a voice command. Using some electromagnets in the device and the stylus itself the S-Pen could be taken out improving one-handed usability, according to Samsung. The device would display a message on the screen or perhaps with a small vibration or even an audible one that such action was performed. Let's remember that patents are not necessarily used, so it might be a while before we see this idea materialized if ever.