Since yesterday it seems the portal has started lagging seriously. Any alerts on your side?
October 9, 2013
Oral exercises not occurring on mobile application
Why doesn't mobile application show lesson descriptions like they do through the web portal?
Explanation of grammatical rules in Duolingo mobile application
beep sound turn off for ipad application
[solved] Don't log in here from the android application on nexus7(2012)
Android application has different number of lessons under one circle
Disabling all sounds on mobile application
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