Apple issued iOS 4.0.1 on Thursday for iPhone, improving the accuracy of the handset’s signal display strength. The installer information succinctly states that iOS 4.0.1 will improve "the formula to determine how many bars of signal strength to display." Apple said that iOS 4.0.1 is the only fix in the update by now.

Despite the change in height of the bars, this update is only cosmetic, and does not change the hardware issue that has drawn the ire of Apple fans and detractors alike. Apple will presumably discuss this issue in further detail at their special iPhone 4 press event, which will be held tomorrow at 10AM Pacific. Besides iOS 4.0.1, Apple also released iOS 3.2.1 for the iPad.