Neither Freud nor Jung had anything to say about cellular phones. However, as they become more prevalent they are obviously making their way into people's dreams. Cell phones have changed from being a symbol of status to a symbol of security. We feel a sense of connection to our resources when the cell phone is nearby. If your dream includes a cell phone, you are probably seeing yourself as connected-or desiring connection with additional opportunities.
There also may be a sense of wanting to change one's social status to necessitate use of a cell phone. Try to discern who you are calling and under what circumstances, as the phone may have a lot of symbolic lifeline or security image to it as well.
Does it feel like a social crutch in your dream, or a helpful tool?
Is it tying you down ... ringing incessantly and keeping you from experiencing a sense of peace in your sleep?