Abstract: A location swapping application running on a first client device scans for location information broadcast by other client devices in proximity to the first client device, the first client device having current location information comprising first location coordinates and a first timestamp. The first client device receives shared location information from a second client device, the shared location information comprising second location coordinates and a second timestamp and compares the second timestamp to the first timestamp. If the location swapping application determines that the second timestamp is more recent than the first timestamp, the application updates the current location information to replace the first location coordinates with the second location coordinates.

Abstract: A proximity detector miming on a server receives a request from an origin device to identify a proximity history of the origin device with one or more target devices and retrieves context information from the origin device and from the target devices. The proximity detector compares the context information from the origin device to the context information from the target devices that is within a time threshold of the context information from the origin device and generates a list of a subset of the target devices that satisfy a proximity threshold with respect to the origin device based on comparing the context information that is within the time threshold. The proximity detector generates an ordered list of events, each event indicating when a target device satisfies the time threshold and the proximity threshold with respect to the origin device, and provides the ordered list of events to the origin device.

Abstract: A proximity detector miming on a server receives a request from an origin device to identify a proximity history of the origin device with one or more target devices and retrieves context information from the origin device and from the target devices. The proximity detector compares the context information from the origin device to the context information from the target devices that is within a time threshold of the context information from the origin device and generates a list of a subset of the target devices that satisfy a proximity threshold with respect to the origin device based on comparing the context information that is within the time threshold. The proximity detector generates an ordered list of events, each event indicating when a target device satisfies the time threshold and the proximity threshold with respect to the origin device, and provides the ordered list of events to the origin device.