The vaadin based forums are a nice show case of vaadin tech however they really don’t work on a mobile phone.
I’ve got a samsung galaxy s3 and the performance on a mobile phone makes the forums unusable.
HTC One user here - and couldn’t agree more :). The forum is quite slow and even crashes from time to time both on the android browser and on chrome. Additionally, the links to threads do not seem to work every time when clicked.