Slate form factor is the most popular form factor for smartphones currently. They are apt for touch enabled gadgets that usually have very minimal physical buttons.
SIM: Dual SIM (Mini-SIM, Dual stand-by)
SIM or Subscriber Identity Module is used to identify and authenticate a device over a network. They also come with small storage space allowing you to store small number of Contacts and messages. Mini SIM is 25 mm by 16 mm in dimensions.
Android is an Open Source Mobile Operating System by Google for touchscreen devices. Each OEM (Original Equipment Manufacturer, e.g.: Samsung, LG, HTC) can use Android for free and tweak it for their device. There are more than 8 versions till date, latest one being Android Kit-Kat. This phones runs on Android 4.1.2 Jelly Bean.
Display type: TFT
TFT[Thin Film Transistor] is a liquid crystal display technology and is good in terms of response and image quality. However this display consumes a lot of power and is expensive. This display is generally considered below average compared to the displays available in market.
Touchscreen: Capacitive touchscreen
Capacitive screens use electrodes to sense the touch of an object that simply has the dielectric value different than that of air. This gives the capacitive screens a slighter edge with respect to sensitivity of the screen. Even a small swipe by the tip of a finger is enough to generate a response whereas its counterpart (resistive touch) requires a heavy touch to get the necessary response.
Pixel density: 176 PPI (Pixels Per Inch)
Pixel density (PPI) gives you the number of pixels per inch of diagnol size. For good clarity (at 100% zoom), minimum acceptable PPI is around 300. Anything lower than 225 is considered below average.