I think the bugs category could easily be used as a quite good bug tracker. It just has to be maintained a little better.
First us moderators should go through all the bugs and move all topics that are not really bugs to another category. (E.g. I believe we established that the ghost touches are not a software bug but a hardware issue, right?)
Then a software employee should go through all the open topics in the category and comment whether the bug is recognized, is being worked on or was fixed already. (I'm guessing that employee would be @keesj, since he's the only one regularly posting in the bugs category)
When a bug has been fixed the topic should be closed with the note: "This bug was fixed with Fairphone OS 1.x.x..."
We currently have 36 topics in the bugs category, 15 of which are already closed, so I think this would be manageable.
EDIT 1: Maybe we could also add status tags to bug topics, like [fixed], [fix in beta testing], [soon to be fixed], [recognized] and [unknown].
EDIT 2: This is what a structured bug report could look like.