Well, at least it didn't get a reply.
The iOS companion app was done by a GSoC student who is no longer an active contributor to Subsurface, and none of the active developers really have taken on maintaining it. It mostly works and appears good enough, so I guess it's one of those "as is" applications.
Your comments below seem valid - but I don't think this is likely to get fixed.
Our focus now is not on the companion apps, anyway, we have more interesting goals: a fairly full featured Subsurface mobile app.
/D