To help frame an image, trying turning on the Grid. To do so, open the Settings app, select Photos & Camera, then turn on the Grid option.

enable-grid

This superimposes a set of lines that splits the screen into nine sections, so you can adhere to the ‘rule of thirds’ (line your subjects up on these lines to make a more appealing image). The grid itself won’t show up on any of the photos.

grid-2