Why did the panorama option disappear? When I got my phone, I could take panorama pictures.

Then the option disappeared. What gives?

If I remember correctly, there was simply an option on this tool tray:


(click screenshot for larger variant)
On my S4 with Verizon's version of Lollipop, this option isn't in the settings menus; it's one of the entries under the "Mode" button on the actual viewfinder screen.