I know this thread is a little old but I thought I'd share a tip I learned last night. This app runs on x86 as well as ARM (RT) but it's very limited. As the OP mentions, it's a viewer and not much else. The mobile version on Android and iOS have some editing tools but they're rudimentary at best. The major letdown is the inability to load X-Refs, which as we all know is very important. On RT devices such as my Surface 2, you can't view .dwg files on IE due to the fact that it doesn't support OpenGL but on x86 devices you can use Firefox to view files at
A360 - Home.
But all is not lost. If you go to
https://client.autocad360.com on any RT device, you use the same login from the app and you have all the tools available to you. There's a link to Autocad WS that takes you to the full editing site where you can load X-Refs and everything. Just for s***s and giggles I tried to do the same on my G3 and iPhone 5 and it only takes you to the "get the app" page. I tried it on Chrome (both platforms), Safari and the stock Android browser to be sure. It didn't matter if the "click for desktop" option was used, it still took you to the app page.
Now I can say that RT is capable of something that neither Android or iOS can do. Apps? We don't need no stinking apps.