Methods, devices and systems for wireless communication. A device user defines a list of contacts and receives a collective indication of which contacts are located within a neighborhood of the device. The neighborhood is defined at the device, for example by the device itself or by the user. A plurality of device users define respective user profiles including user attributes. One of the users defines a target attribute, and receives an indication of which other users that have that attribute have devices in the first user's neighborhood. The devices communicate among themselves either indirectly, for example via cellular base stations, or directly.