I remember that not so long ago all the apps had a limited, read-only functionality. I wonder if it has changed?
Is there an Android app that allows you to post questions/comments to SE sites?
The stack exchange API officially does not support posting questions or answers, but it does allow posting comments.
So you can install the StackX app and use it to comment on posts.
There is also an Official Android App in alpha development. It looks like they are still taking sign-ups for