WPPA+ is responsive by nature, provided that you have Table I-A1 set to auto.
This setting is the default for the system. You can overrule the size by specifying it in the shortcode.
This way you can have a responsive display in a static system (Table I-A1 set to a numeric value and size="auto" in the shortcode) or a static display in a responsive theme (Table I-A1 set to auto and e.g. size="400" in the shortcode).
If you specified auto as explained above, the full available width will be used. Also on responsive themes when you change the width of the browser window, or you rotate a mobile device, the size of the display will change so the full width will stay filled.
[wppa type="cover" album="1"][/wppa] Table I-A1 is set to auto.
First album
If you specify a fraction in the shortcode, the width of the display will be that part of the available column width.
This example: 0.8 produces a display width of 80% of the available column width.
You may wish to align the display left, center or right.
[wppa type="thumbs" album="1" size="0.8" align="center"][/wppa]
If you specify a pixelsize, the width will be set to that size, even on (the most) responsive themes.
[wppa type="thumbs" album="1" size="400" align="right"][/wppa]
When displaying single photos, make sure your display files have large enough pixelsizes to fill the width of the display. If you downsize during upload/import, the max width of the display files will be as set in Table I-A3. In slideshows, the photos will never be displayed larger than tey are, unless you tick Table I-B3.
[wppa type="photo" photo="4257"][/wppa]
A photo with a large enough pixelsize ( 1620 x 1080 )
[wppa type="photo" photo="4256"][/wppa]
The pixelsize of this photo is only 200 x 133