As far I know, there was no other change. When first installed, the app stubbornly refused to find the lamp no matter what I did. I then deleted it, reinstalled it and now it works like magic.
I deleted the app because I was going to install it on an Android phone and didn't want any interference. The Android turned out to be too old to install anything on it but when I reinstalled the app on the iPhone, it just found the lamp as if there had never been any problem.