Abstract: A user activity, which may be a debit or credit card transaction or an online access, is approved, or proximity between two users is confirmed, based on a response or other acknowledgement from a mobile subscriber terminal. The mobile subscriber terminal acknowledgement is generated in response to a query from an authorizing entity associated with the debit or credit card, or another mobile subscriber terminal, and indicates whether or not the mobile subscriber terminal is within a maximum allowable radius from a specific location included in the query. It is noted that no specific location information is included in the mobile subscriber terminal acknowledgement. An application downloaded to the mobile subscriber terminal may generate the above-described acknowledgement.

Abstract: A user activity, which may be a debit or credit card transaction or an online access, is approved, or proximity between two users is confirmed, based on a response or other acknowledgement from a mobile subscriber terminal. The mobile subscriber terminal acknowledgement is generated in response to a query from an authorizing entity associated with the debit or credit card, or another mobile subscriber terminal, and indicates whether or not the mobile subscriber terminal is within a maximum allowable radius from a specific location included in the query. It is noted that no specific location information is included in the mobile subscriber terminal acknowledgement. An application downloaded to the mobile subscriber terminal may generate the above-described acknowledgement.

Abstract: A user activity, which may be a credit card transaction or an on-line access, is approved based on the user's location at the time of the transaction or access. If the transaction or access is denied, the user may call or send a text message to the authorizing entity to permit the authorizing entity to determine the user's location. Then, the authorizing entity transmits a request to locate the user and receives location data indicating the location of the user in response thereto. If the user location is within a predetermined proximity to the location of the user activity, the user activity is authorized.