Any prognosis on when the mobil interface will be fixed?
I can currently access the Hungarian course on my iPhone or iPhone only if I turn off the device, restart, and reset the wifi interface. At the end of one lesson I get the screen asking me if I would like some other language -- reminding me of The Onion story about Rosetta Stone Hungarian (http://www.theonion.com/article/first-disk-of-rosetta-stone-hungarian-just-urges-l-28421) -- and have to shut down and restart again. I've missed some days when I don't have access to a laptop. Any idea when this will be fixed?
Use a browser on your device to access this website. It's not quite so convenient as the app, but there is a mobile version of the website optimised for small screens; Hungarian isn't supported by the app yet (even though all the content is there), but it's supported by the mobile website (plus the content is better on the website).
I doubt the course will be released onto the app terribly soon, as there still seem to be a lot of missing translations, and these will probably still be generating too high a level of reports for Duolingo to release it for the time being. Consider that Vietnamese has been out for very much longer than Hungarian, and it is still not on the iOS app.
Hungarian is not officially supported by the app yet as it's in early beta.
As far as I know, there's a certain quality threshold which has to be passed before courses are added to the app (in terms of number of reports per 100 users or something like that), and in the current state of the course, that will still take a while as many sentences are missing correct translation alternatives which are being reported all the time.
So if the course works in the app, it's a "bug", and you shouldn't rely on it.
For now, only the website version of the Hungarian course is supported.
As garpike said, you can visit the website on the browser of your mobile device if you want to use that device rather than a laptop/PC.
Or if you want to do Hungarian through the app, wait until it's officially released for the app - perhaps in three to six months.
It's not something that needs to be fixed, it simply isn't supported on the app yet - your access is a loophole that's an error in the system.
When it's added to the app properly, you'll be able to access it. In the meantime, access the browser version on your mobile device.