It’s easy to photographers and create stereoscopic photo pairs with a smartphone when the subject is still or not moving quickly. The downside is that smartphone cameras have an unnaturally large depth of field so everything is in focus.
A more artistically pleasing photo has some portion of the foreground and or background out of focus. Newer smartphones can generate this out of focus effect but using data data from two slightly offset image sensors. (The latest Apple phone with its 3D sensor array can generate the necessary data.)
When the bokeh images are combined with the left-right layout, the end result is a much more natural stereoscopic image.