No matter which of these you use, the rules of photography are the same:
1/. Decide exactly what you are going to photograph and decide what sort of background setting will you use and what don't you need.
2/. Frame the photograph. (Sort out what's needed and what is not needed to be in the picture).
3/. If you are photographing people ensure they are "in the frame" and not obscured in the distance. Avoid blurry main subjects. You can blur out the background if required, so long as your subject is in focus.
4/. When shooting it is preferable to use the landscape mode (wider area coverage), to fill the frame with a more interesting shot.
Verticals should only really be used for a portraits of one person or two, or when photographing something really vertical - such as a tall building (and then preferably also take a landscape shot to compliment). Avoid at all times vertical photos where a landscape shot would give better (more) detail.
The above especially applies to mobile phone photos which you want to move off your phone for displaying!