I released my first solo iPhone app last week that calculates 12V Marine and Boat Battery usage. I had tested it vigorously on the simulator and on my iPhone, and when I was
Is more a hint than an answer.. but, as I already said in comments: you can check the different behavior between Release and Debug version.
This different "behavior" has been seen in the past. Is given by "Optmization Level" setting. Debug version is set to None [-O0], while the Release version is set to Fastest, Smallest [-Os].
An example here .. here another ..