Xiaomi Redmi Note 4 is a new generation smartphone powered by an 8 core Snapdragon 625 processor, 5.5 inch screen with 1080p resolution and MIUI 8 (an interface on top of Android). This could be considered a flagship killer because of the good specs as mentioned above.
It has a good price and for this money we get a device with good specifications and good software. The software is MIUI (as mentioned above) and is an alternative to TochWiz from Samsung.
This smartphone is available in many colors (from gold to grey).
It has a deca core CPU named Helio X20 from Mediatek. This is a very good CPU and other thing to consider on the specs side are the 3GB of RAM, the 64GB ROM (internal memory) and the support of micsro SD cards. The specs may be different for other variants. Also, about the processor you should know that it has the performance increades by 62% and the power consumption reduced to 30% compared to Helio X10 (an octa core CPU from the same manufacturer).
Like on other phones, the screen is one with a nice 2.5D design named Arc Screen Design.
The main camera is a good one because of the 13MP. So, the pictures will be very clear.
It comes with good back case made of metal so that the phone will be more resistant compared to the models with glass or ceramic black.
The OS is not the newest and the CPU is Mediatek. There is a Snapdragon version but it might cost more. About the OS you should know that it is Android 6, but it can be upgraded to 7.
Because of the 5.5 inch screen size this device is considered to be a phablet (combination between tablet and smartphone). I consider this phone to be a ver good one, even a flagship killer.
It has the most important features like good cameras, fingerprint reader (on the back), good screen and good battery.