At work, we use Seekbeak to view panorama images. We finally tried Enscape's own panorama web viewer. It's a simple viewer that works. However, there's a big problem: you cannot look up or down on iOS devices, using a finger. You can only rotate around. This problem doesn't occur with Seekbeak, so it's not iOS limitation. In the Enscape panorama web viewer on the computer, you can look/down, using a mouse; hopefully this problem on iOS can be fixed soon.
(understand you can do this with motion sensor, but it's just a gimmick that is only fun for a few seconds. After a while, we noticed pretty much everyone prefers using a finger to look / down / rotate when presented on Seekbeak)