There are friends, colleagues or even partners who do not notice it, when they dominate others in a conversation. They just talk too much. A little iPhone app helps. The iPhone is placed between two people having a conversation and learns to separate the two voices. At intervals of 1, 2 or 5 minutes you see different lengths of red and blue bars that show what percentage of time each speaker was talking. Nobody has to be unpleasantly exhorted – from time to time everyone will have a cursory glance at the Talk-o-Meter and adapt if he is talking too much. Gentle biofeedback works.