As mentioned in the forum post –
you can have any number of iPhone sliders on a page and you just specify the image URLs as a comma separated string as an argument to an iPhone slider shortcode. In your case, you would have two instances of this shortcode and since the slider is responsive, you do not have to worry about size of the slider container. How you want to present it is up to you – depends on how you want to market your app.
BTW, I am also releasing this week an Galaxy S4 slider and HTC One Slider for Android App developers. I mentioned this since you can go for an iPhone Slider and an S4/HTC One slider instead of two iPhone sliders. The screenshot aspect ratio will vary slightly to accommodate the differing sizes.