Dynamic range the range of light intensities a camera can capture in the one photo while preserving detail tends to be a weak point in smartphone cameras. In scenes with both dark and bright areas, such as a shadowed forest, its difficult to capture detail in the shadows and highlights at the same time. This is where HDR mode, or high dynamic range mode, comes into play.
HDR mode takes two images of different exposures near-simultaneously, and then combines them to produce one image that has higher dynamic range than the sensor can normally achieve. On most smartphones, this is something you can and should enable when the scene youre photographing has widely varying contrast. The difference in photos can be vast, especially on Samsung smartphones where the HDR mode is particularly effective.