A method of sharing data between a sending mobile device and a receiving mobile device, the method comprising performing, by the sending mobile device: storing, in a memory of the sending mobile device , a data item; receiving, at a user interface of the sending mobile device , user input indicating a sharing session for sharing the data item; broadcasting, via a first wireless protocol of the sending mobile device , an advertisement signal that includes a first authentication tag of the sending mobile device ; receiving, via the first wireless protocol from the receiving mobile device , a second authentication tag of the receiving mobile device ; authenticating the receiving mobile device using the second authentication tag; communicating, using the first wireless protocol, one or more ranging settings with the receiving mobile device for a ranging operation to be performed using a second wireless protocol; transmitting, using the second wireless protocol, a first set of one or more pulses in a ranging request message to the receiving mobile device in accordance with the one or more ranging settings, wherein the second wireless protocol uses a pulse width that is less than a pulse width used by the first wireless protocol; receiving, using the second wireless protocol, a second set of one or more pulses in one or more ranging response messages from the receiving mobile device ; determining distance information corresponding to one or more transmission times of the first set of one or more pulses and one or more reception times of the second set of one or more pulses; receiving, via input to the user interface, a user selection of the receiving mobile device to share the data item, the selection made in accordance with the distance information; and transmitting the data item in response to the selection of the receiving mobile device . storing, in a memory of the sending mobile device , a data item; receiving, at a user interface of the sending mobile device , user input indicating a sharing session for sharing the data item; broadcasting, via a first wireless protocol of the sending mobile device , an advertisement signal that includes a first authentication tag of the sending mobile device ; receiving, via the first wireless protocol from the receiving mobile device , a second authentication tag of the receiving mobile device ; authenticating the receiving mobile device using the second authentication tag; communicating, using the first wireless protocol, one or more ranging settings with the receiving mobile device for a ranging operation to be performed using a second wireless protocol; transmitting, using the second wireless protocol, a first set of one or more pulses in a ranging request message to the receiving mobile device in accordance with the one or more ranging settings, wherein the second wireless protocol uses a pulse width that is less than a pulse width used by the first wireless protocol; receiving, using the second wireless protocol, a second set of one or more pulses in one or more ranging response messages from the receiving mobile device ; determining distance information corresponding to one or more transmission times of the first set of one or more pulses and one or more reception times of the second set of one or more pulses; receiving, via input to the user interface, a user selection of the receiving mobile device to share the data item, the selection made in accordance with the distance information; and transmitting the data item in response to the selection of the receiving mobile device . <EOS>