If your phone is in color one minute and black-and-white the next, there could be a temporary issue with the OS or an app. A simple restart could bring color back to your phone.

Unless you know for sure your phone is made up of nylon, polypropylene, polyethylene, or polyester plastics (which are better at resisting WD-40's effects) it's best not to take the chance.

That said, if you drop your $1,200 iPhone, you might be glad you paid upfront for AppleCare+ ($199 for two years when signing up for coverage, then $29 to fix a broken screen).