In one example, a method includes receiving a first group of indications associated with a first group of modalities and a second group of indications associated with a second group of modalities. The method also includes determining a confidence value for at least one modality of the first or second groups of modalities based at least in part on an indication associated with the at least one modality. The confidence value may indicate a likelihood that a first user associated with the first remote computing device is within a physical presence of a second user associated with the second remote computing device. The method may also include, performing an operation to indicate that the first user associated with the first remote computing device is within a physical presence of the second user associated with the second remote computing device.