Could bees be disappearing due to magnetic influence from cell phones?

Very unlikely. There have been man made magnetic fields in the environment from many sources for many decades before cell phones. Spark blug emissions and the magnets in TVs are just a couple of examples. The present theory is that pesticides and antibiotics have disrupted the bacterial balance. That is harmful bacteria specis that were kept in check by competition with other non harmful specis aren't now because of pesticides and antibiotics. This is supported by the finding that harmful bacteria found in bees and elsewhere in the enironment is increasing.

OK seems reasonable. Do you know if they tend to find masses of dead bees in places? You would think if that was the reason that bees would die in mass when those chemical were present. I thought this was more that bees went missing. If its the latter then it would probably mean somehow their navigation was being thrown off. I believe that they are similar to birds, where they use the angle of the earth's magnetic forces as a key to navigation.

Bees remove the dead and sick from the hive. They simply carry them away and drop them. I've seen them do it. The bees aren't going missing. They are found with infection in them. The issue now is how to protect them from the infections. It's only a problem because we aren't likely to get farmers to stop using pesticides and antibiotics.