A system, wherein the system comprises a first electronic device and a second electronic device, wherein the first electronic device is configured to display a first interface, wherein the first interface is an account login interface or an account registration interface of a first application; the first electronic device is further configured to send first request information to the second electronic device in response to detecting an operation that a user performs account login or account registration for the first application by using a second application, wherein the first request information is used to request the second application on the second electronic device to perform authorization for the first application; the second electronic device is configured to send, based on the first request information, second request information to a server corresponding to the second application, wherein the second request information is used to request first information, the first information is to be used by the first electronic device to request information about a first account, and the first account is a login account of the second application on the second electronic device; the second electronic device is further configured to receive the first information sent by the server, and send the first information to the first electronic device; the first electronic device is further configured to request the information about the first account from the server based on the first information; and the first electronic device is further configured to receive the information about the first account that is sent by the server, and perform account login or account registration for the first application based on the information about the first account; characterized in that the first electronic device is further configured to: send a query request before sending the first request information to the second electronic device, wherein the query request is used to request an electronic device that receives the query request to determine whether the second application is installed; and receive a first response sent by the second electronic device, wherein the first response indicates that the second application is installed on the second electronic device, wherein the first electronic device sends the first request information to the second electronic device in response to receiving the first response. the first electronic device is configured to display a first interface, wherein the first interface is an account login interface or an account registration interface of a first application; the first electronic device is further configured to send first request information to the second electronic device in response to detecting an operation that a user performs account login or account registration for the first application by using a second application, wherein the first request information is used to request the second application on the second electronic device to perform authorization for the first application; the second electronic device is configured to send, based on the first request information, second request information to a server corresponding to the second application, wherein the second request information is used to request first information, the first information is to be used by the first electronic device to request information about a first account, and the first account is a login account of the second application on the second electronic device; the second electronic device is further configured to receive the first information sent by the server, and send the first information to the first electronic device; the first electronic device is further configured to request the information about the first account from the server based on the first information; and the first electronic device is further configured to receive the information about the first account that is sent by the server, and perform account login or account registration for the first application based on the information about the first account; characterized in that the first electronic device is further configured to: send a query request before sending the first request information to the second electronic device, wherein the query request is used to request an electronic device that receives the query request to determine whether the second application is installed; and receive a first response sent by the second electronic device, wherein the first response indicates that the second application is installed on the second electronic device, wherein the first electronic device sends the first request information to the second electronic device in response to receiving the first response. send a query request before sending the first request information to the second electronic device, wherein the query request is used to request an electronic device that receives the query request to determine whether the second application is installed; and receive a first response sent by the second electronic device, wherein the first response indicates that the second application is installed on the second electronic device, wherein the first electronic device sends the first request information to the second electronic device in response to receiving the first response.