A method, comprising: transmitting, from a first computing device to a computer system , a request to create a reminder , wherein the computer system is configured to, in response to receiving the request: notify a second computing device of the reminder ; receive, from the second computing device, confirmation that the second computing device will allow proximity communications with the first computing device ; generate a reminder identifier associated with the reminder ; and provide to the first computing device and the second computing device the reminder identifier , wherein the first computing device and the second computing device are configured to store the reminder identifier in response to receiving the reminder identifier ; identifying, by the first computing device, a geographic proximity of the second computing device by detecting, by the first computing device, a broadcast from the second computing device of the reminder identifier, the broadcast using a short-range communication protocol having a maximum range of less than about one hundred meters ; establishing, by the first computing device, direct short-range communications with the second computing device, the first computing device and the second computing device being able to communicate with one another using a short-range communication protocol ; receiving, by the first computing device, an indication that the first computing device shares the reminder identifier with the second computing device ; and receiving, by the first computing device, information relevant to the first computing device regarding the second computing device based on the shared reminder identifier . transmitting, from a first computing device to a computer system , a request to create a reminder , wherein the computer system is configured to, in response to receiving the request: notify a second computing device of the reminder ; receive, from the second computing device, confirmation that the second computing device will allow proximity communications with the first computing device ; generate a reminder identifier associated with the reminder ; and provide to the first computing device and the second computing device the reminder identifier , wherein the first computing device and the second computing device are configured to store the reminder identifier in response to receiving the reminder identifier ; notify a second computing device of the reminder ; receive, from the second computing device, confirmation that the second computing device will allow proximity communications with the first computing device ; generate a reminder identifier associated with the reminder ; and provide to the first computing device and the second computing device the reminder identifier , wherein the first computing device and the second computing device are configured to store the reminder identifier in response to receiving the reminder identifier ; identifying, by the first computing device, a geographic proximity of the second computing device by detecting, by the first computing device, a broadcast from the second computing device of the reminder identifier, the broadcast using a short-range communication protocol having a maximum range of less than about one hundred meters ; establishing, by the first computing device, direct short-range communications with the second computing device, the first computing device and the second computing device being able to communicate with one another using a short-range communication protocol ; receiving, by the first computing device, an indication that the first computing device shares the reminder identifier with the second computing device ; and receiving, by the first computing device, information relevant to the first computing device regarding the second computing device based on the shared reminder identifier . <EOS>