For this Bokeh/ Blur effect you will have to use a camera and cannot be taken using a mobile. You may though use the cheat apps which blur some part of the picture but still getting the quality would be poor. While the other tip of one third still can be used using your mobile.
The rule of one third and Bokeh Effect
The rule of thirds is a “rule of thumb” or guideline which applies to the process of composing visual images such as designs, films, paintings, and photographs. The guideline proposes that an image should be imagined as divided into nine equal parts by two equally spaced horizontal lines and two equally spaced vertical lines, and that important compositional elements should be placed along these lines or their intersections. Proponents of the technique claim that aligning a subject with these points creates more tension, energy and interest in the composition than simply centering the subject.
The picture without the rule of third cropped to put the flower in the center.
The other effect is the bokeh effect for which you need to put your camera on manual settings and select. The term comes from the Japanese word boke , which means “blur” or “haze”. The most preferred lens for such photography is the 50mm 1.8 F prime lens. The reason for it is that one in lay man terms a low F value increases the cost of the lens and this is one of the cheapest lens in that category. So select a F 1.8 value on your lens take a photo and see the Bokeh effect.