If you already have the cookie, you can use it to authenticate the service. You can try deploying the app on the same domain as service. This has nothing to do with Tiggzi.
YouTrack rest API
After all of the above and if anyone else is running into the same problem I found this page:
http://help.gotiggr.com/documentation...
One of the options on that page is running Google chrome with security disabled, which fixes the above problem.
Would have been great if someone had pointed me in the direction of that page.
YouTrack rest API
The new link is here: http://docs.tiggzi.com/documentation/... (the one you posted covers the old builder).
Running Chrome with security disabled is a local workaround. Users using the app most likely won't do that. An better solution is to support cross-domain services calls, or JSONP.
YouTrack rest API
So you knew about that page all along! This is merely so I can test the app while trying to develop it in the browser without having to deploy the .apk to a device or emulator every time.
YouTrack rest API
Yes, I knew about the page 
. You can use also Tiggzi Proxy.
YouTrack rest API
I would have expected you too, considering your role. The purpose of me posting here is for some help and if you don't want to give it, then maybe you are in the wrong role
YouTrack rest API
The page covers Ajax calls security, cross-domain calls and other alternatives, but not cookies. That's why I didn't share it earlier. If the cookie issue is solved -- that's great.