Hello Seema: There are two players in Articulate Storyline 360: Modern and Classic.
When you select the Modern player, Storyline 360 automatically formats your responsive course with a range of options/views: desktop, tablet landscape, tablet portrait, phone landscape, and phone portrait. These various views illustrate exactly how your course will appear when viewed on a desktop, tablet, and phone. 360 is a very different product from Articulate 3. If you use Storyline for all of your course production, I think it would be a good investment to make the jump to Storyline 360. You won't be disappointed.
Kind regards,
Robert