As you may or may not know, I am super into technology.
In this video the presenter (MKBHD), was explaining how smartphone cameras work.
At the start of the video he fixed a common misunderstanding, the more megapixels, the better the camera.
The things that matter are the sensor, image stabilization. aperture, and processing.
The bigger the sensor the better. For example the Nokia Lumia 1020, has a HUGE sensor.
Image stabilization comes in two forms: Digital Image Stabilization (DIS), and Optical Image Stabilization (OIS). OIS is better because, it has a gyroscopic device that stabilizes the image while DIS is computer generated.
Aperture describes the amount of light let in.
As you can see f/1.4 has a larger opening to let more light in.
Processing is based on how the smartphone takes in the image. For example some phones may over expose the image and Some may under expose.