information:classification
Space constraints

Typically smartphones have at least one main rear-facing camera and a lower-resolution front-facing camera for " selfies " and video chat. Owing to the limited depth available in smartphones for image sensors and optics, rear-facing cameras are often housed in a "bump" that is thicker than the rest of the phone. Since increasingly thin mobile phones have more abundant horizontal space than the depth that is necessary and used in dedicated cameras for better lenses, there is additionally a trend for phone manufacturers to include multiple cameras, with each optimized for a different purpose (telephoto, wide angle, etc.).

Viewed from back, rear cameras are commonly located at the top center or top left corner. A cornered location benefits by not requiring other hardware to be packed around the camera module while increasing ergonomy, as the lens is less likely to be covered when held horizontally.

Modern advanced smartphones have cameras with optical image stabilisation (OIS), larger sensors, bright lenses, and even optical zoom plus RAW images. HDR, " Bokeh mode" with multi lenses and multi-shot night modes are now also familiar. Many new smartphone camera features are being enabled via computational photography image processing and multiple specialized lenses rather than larger sensors and lenses, due to the constrained space available inside phones that are being made as slim as possible.