EXIF stands for Exchangeable Image File Format, and is a standard for storing information created by JEIDA (Japan Electronic Industry Development Association) to encourage interoperability between image devices, including camera phones, those using JPEG compression.

Latest model of camera phones use the EXIF annotation, storing information on the image such as shutter speed, exposure compensation, F number, what metering system was used, if a flash was used, ISO number, date and time the image was taken, whitebalance,  and resolution.

Refer to your image editing software manual before making any modification to images captured by your camera phone,  EXIF data may be lost when saving a file after editing.  Make sure you should always preserve your original image and use "Save As" after editing it.